Method and apparatus for thoracoscopic intracardiac procedures

ABSTRACT

Devices, systems, and methods are provided for accessing the interior of the heart and performing procedures therein while the heart is beating. In one embodiment, a tubular access device having an inner lumen is provided for positioning through a penetration in a muscular wall of the heart, the access device having a means for sealing within the penetration to inhibit leakage of blood through the penetration. The sealing means may comprise a balloon or flange on the access device, or a suture placed in the heart wall to gather the heart tissue against the access device. An obturator is removably positionable in the inner lumen of the access device, the obturator having a cutting means at its distal end for penetrating the muscular wall of the heart. The access device is preferably positioned through an intercostal space and through the muscular wall of the heart. Elongated instruments may be introduced through the tubular access device into an interior chamber of the heart to perform procedures such as septal defect repair and electrophysiological mapping and ablation. A method of septal defect repair includes positioning a tubular access device percutaneously through an intercostal space and through a penetration in a muscular wall of the heart, passing one or more instruments through an inner lumen of the tubular access device into an interior chamber of the heart, and using the instruments to close the septal defect. Devices and methods for closing the septal defect with either sutures or with patch-type devices are disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of application Ser. No.09/411,095, filed Oct. 4, 1999, which is a continuation of applicationSer. No. 08/643,898, filed May 7, 1996, now issued as U.S. Pat. No.6,079,414, which is a divisional of application Ser. No. 08/425,179,filed Apr. 20, 1995, now issued as U.S. Pat. No. 5,797,960, which is acontinuation-in-part of application Ser. No. 08/163,241, filed Dec. 6,1993, now issued as U.S. Pat. No. 5,571,215, which is acontinuation-in-part of application Ser. No. 08/023,778, filed Feb. 22,1993, now issued as U.S. Pat. No. 5,452,733. The complete disclosures ofthese applications are hereby incorporated herein by reference for allpurposes.

FIELD OF THE INVENTION

[0002] The present invention relates generally to less-invasive surgeryof the cardiovascular system. More specifically, the invention relatesto thoracoscopic devices and techniques for performing surgicalprocedures within the heart and great vessels while the heart isbeating.

BACKGROUND OF THE INVENTION

[0003] Tens of thousands of people are born each year with congenitaldefects of the heart. Some of the more common types of congenitalcardiac defects include atrial septal defect (ASD), ventricular septaldefect (VSD), and patent ductus arteriosis (PDA). An ASD is a hole inthe cardiac septum between the left and right atria, while a VSD is ahole in the septum between the left and right ventricles. Patent ductusarteriosis is incomplete closure of the opening between the pulmonaryartery and the aorta that is present during fetal development. Theseconditions may cause blood to abnormally shunt from the right side ofthe heart to the left side of the heart without being properlyoxygenated in the lungs, so that the body tissues supplied by the bloodare deprived of oxygen. In addition, blood in the left side of the heartmay shunt back to the right side through the defect rather than beingpumped into the arterial system, causing abnormal enlargement of theright chambers of the heart. defects may require a patch of polyester,expanded polytetrafluoroethylene, or a portion of the patient's ownpericardium to be sutured into the heart to cover and occlude thedefect.

[0004] Ordinarily, such surgery is performed using open-chest techniqueswhile the heart is under cardioplegic arrest and circulation ismaintained by cardiopulmonary bypass. Using such techniques, a grossthoracotomy is created in order to gain access to the heart and greatvessels, facilitating clamping and cannulation of the aorta for inducingcardioplegic arrest, and allowing instruments to be introduced into thechest cavity and into the heart to perform the surgical repair. Thenecessity of stopping the heart significantly heightens the risksattendant such procedures, particularly the risks of causing ischemicdamage to the heart muscle, and of causing stroke or other injury due tocirculatory emboli produced by aortic clamping and vascular cannulation.In addition, the creation of a gross thoracotomy produces significantmorbidity and mortality, lengthens hospital stay and subsequentrecovery, increases costs, and worsens the pain and trauma suffered bythe patient. Moreover, many congenital defects are repaired in childrenunder the age of ten years for whom the morbidity and mortality ofopen-chest surgery and cardioplegic arrest can be even greater than forolder patients.

[0005] In an effort to avoid the necessity of grossly opening the chestand stopping the heart, a number of intravascular devices have beendeveloped for repair of ASD's, VSD's, and PDA. For example, U.S. Pat.No. 3,874,388 to King et al. discloses an intravascular deliverycatheter introduced intraluminally from a peripheral vein into the rightside of the heart which can be used to position an artificialumbrella-like patch across a septal defect and to anchor the patch tothe cardiac septum. Other intravascular delivery devices and artificialpatches for the repair of septal defects can be seen in U.S. Pat. No.5,334,217, U.S. Pat. No. 5,284,488, U.S. Pat. No. 4,917,089, U.S. Pat.No. 4,007,743, and PCT Application No. PCT/US92/10141.

[0006] While intravascular approaches to the repair of congenitaldefects may provide certain advantages, the most significant of which isthe elimination of the need for gross thoracotomy and cardioplegicarrest, these techniques have suffered from a number of problems. Onesuch problem is the difficulty in manipulating the artificial patchesinto position across a defect using only the proximal end of a long andflexible delivery catheter positioned through a tortuous right lumen.Also problematic is the inadequacy of fixation of endovascularly-placedpatches, creating a tendency of such patches to migrate or embolizeafter placement, which can allow blood to again shunt through thedefect. In addition, once such a patch has been placed and the deliverycatheter detached from the patch, relocating and repositioning the patchwith the catheter is difficult, if not impossible, and may require opensurgical correction. Moreover, in young children, the size of theperipheral vessels is extremely small, and damage to such vessels couldhave serious effects upon the growth of the child. Thus, the size of thedevices which can be introduced through such vessels is greatly limited.

[0007] In addition to ASD, VSD, and PDA, various other types of cardiacdisease also may be diagnosed and treated by intervention within theinterior chambers of the heart. For example, some cardiac arrhythmiassuch as ventricular tachycardias, supraventricular tachycardias, andatrial fibrillation, may be diagnosed by obtaining access into aninterior chamber of the heart and by performing electrophysiologicalmapping to identify abnormal conduction pathways. Once these abnormalconduction pathways are identified, in some cases the disease may betreated by ablating selected cardiac tissue using radiofrequency (RF)energy or a medical laser to eliminate the abnormal pathways. A numberof endovascular approaches have been developed which attempt to allowintracardiac mapping and ablation using catheters introducedtransluminally from peripheral vessels into the heart. Such devices aredisclosed, for example, in U.S. Pat. Nos. 4,960,134, 4,573,473,4,628,937, and 5,327,889. However, endovascular mapping and ablationdevices suffer from many of the same problems suffered by endovascularseptal defect repair devices, including a lack of control and precisepositionability from the proximal end of these highly flexible andelongated devices, the significant size constraints of peripheralvessels, and the inability to position the devices in all potentiallydiseased sites within the heart.

[0008] What are needed, therefore, are devices and methods to enable therepair of ASD, VSD, PDA, and other congenital defects, as well ascardiac arrhythmias and other diseases of the heart, which eliminate theneed for gross thoracotomy and cardioplegic arrest, but which overcomethe forementioned problems with intravascular techniques. The devicesand methods should facilitate a high level of control for precisemanipulation within the heart. The devices and methods should produce aseptal defect or PDA repair which is reliable and long-lasting, andshould not be susceptible to migration, embolization, or reopening of adefect. The devices and methods for septal defect and PDA repair shouldallow the position of a repair patch to be inspected after initialplacement and to be repositioned if necessary. Finally, the devices andmethods should not risk damaging the peripheral vessels of the patient,nor should the size and configuration of the devices be limited by thesize of the patient's peripheral vessels.

SUMMARY OF THE INVENTION

[0009] The invention provides devices and methods that facilitatethoracoscopic access into the interior of the heart while the heart isbeating. This intracardiac access can be used to perform a variety ofdiagnostic and treatment procedures within the heart without the needfor a gross thoracotomy or cardioplegic arrest. The invention providesdevices and methods for the performance of a number of differentprocedures including the repair of ASD, VSD, PDA, and other cardiacabnormalities, electrophysiologic mapping and ablation for the treatmentof cardiac arrhythmias, as well as a variety of other intracardiacprocedures that can be performed thoracoscopically on a beating heart.

[0010] In a first aspect of the invention, a tubular access device isprovided for accessing an interior chamber of a beating heart. Theaccess device includes an elongated tubular body configured to extendpercutaneously through an intercostal space between the ribs of thechest and through a muscular wall of the heart, and an inner lumenextending through the tubular body which provides an access channel intothe heart. In an exemplary embodiment, the tubular access device has alength of at least 10 cm, and the inner lumen has a diameter of at least5 mm. Preferably, the tubular access device is rigid to facilitateresponsive and precise positionability from its proximal end.

[0011] In one embodiment, the access device includes means near a distalend thereof for sealing peripherally around a surrounding penetration inthe muscular heart wall through which the access device is positioned.The sealing means may comprise one or a pair of inflatable balloons, aradially-expandable portion of the tubular body, or a flange at thedistal end of the body. A purse string suture or other tissue-gatheringmeans may be applied to the muscular heart wall surrounding the tubularbody and tightened to prevent blood from flowing through the penetrationaround the access device.

[0012] The invention may further include an obturator positionablewithin an inner lumen of the tubular access device. The obturator mayhave means at its distal end for penetrating the muscular wall of theheart. The penetrating means may comprise a blade, radiofrequencyelectrode, or other type of cutting element. In a preferred embodiment,the obturator further includes means for selectively exposing thepenetrating means, which may include a movable actuator for extendingand retracting the cutting means from the distal end of the obturator.

[0013] The access device may include a hemostasis valve in the innerlumen to prevent blood flow out of the heart through the inner lumen,and to allow instruments to be introduced through the inner lumen whilemaintaining hemostasis in the inner lumen. The hemostasis valve may bedisposed at either the proximal end or the distal end of the accessdevice. Alternatively, when the access device is utilized in thelower-pressure right atrium, right ventricle, or left atrium, the accessdevice may be positioned in a generally vertical orientation so thatblood flow through the inner lumen is prevented by the pressure head ofblood within the inner lumen being greater than the pressure in thecardiac chamber, eliminating the need for a hemostasis valve.

[0014] With the access device positioned through an intercostal spaceand through a wall of the heart, a straight and relatively large channeldirectly into the interior of the heart is available for theintroduction of devices for diagnostic and treatment procedures. In apreferred embodiment, the invention provides systems and methods forrepairing atrial and ventricular septal defects through the inner lumenof the access device. The septal defect repair system includes, inaddition to the above-described access device, a closure means forclosing or occluding the septal defect, and a means for introducing theclosure means through the access device into the interior of the heart.

[0015] In a first embodiment, the closure means comprises a patch thatmay be attached to the cardiac septum to cover and occlude the septaldefect. The patch includes a collapsible frame, and a flexible patchmaterial attached to the frame. The flexible patch material may be anartificial biocompatible material such as polyester or expandedpolytetrafluorethylene, or a portion of the patient's pericardium orother natural body membrane. The frame is configured to support thepatch material at its outer edges in a generally flat configuration, andis sufficiently rigid to retain its shape against the pressure of bloodwithin the heart, while having sufficient flexibility and resiliency tobe collapsible for introduction through the inner lumen of the accessdevice. In an exemplary embodiment the frame comprises a hub and aplurality of spokes extending radially outward from the hub. Acircumferential wire or suture thread extending between the outer tipsof the spokes may be provided to continuously support the outer edges ofthe patch. The hub is a rigid material such as stainless steel, is smallenough to fit within the inner lumen of the access device, and isconfigured to be detachably coupled to the distal end of an deliveryshaft (described below). The spokes are flexible, resilient wires ofNitinol™ or other material exhibiting similar super-elasticcharacteristics. The patch may be mounted to the frame by sutures, heatwelding, adhesive, or other means.

[0016] The patch includes a means for securing the patch to the cardiacseptum. The securing means may comprise a second patch coupled to acentral portion of the first patch and parallel thereto such that onepatch may be positioned through the septal defect on the left side ofthe cardiac septum and the second patch positioned on the right side ofthe cardiac septum, with the outer edges of the two patchescompressively engaging the cardiac septum between them. For example, inthe hub and spoke embodiment describe above, two sets of spokes may bemounted to the hub and a patch mounted to each set of spokes so that thetwo patches are generally parallel to each other and spaced slightlyapart. Alternatively, the securing means may comprise a plurality offlexible wire struts coupled to a central part of the frame such thatthe outer ends of the struts will compressively engage the cardiacseptum on the side opposite that on which the patch is positioned. Likethe patch, the securing means is collapsible to allow introductionthrough the inner lumen of the access device. To facilitate securefixation to the septum, the frame or the securing means may include pinsor spikes pointing generally perpendicular to the patch to partiallypenetrate the cardiac septum when the patch has been positioned acrossthe defect, preventing migration of the patch.

[0017] The patch is introduced into the heart and positioned across theseptal defect by means of a rigid delivery shaft which may be positionedthrough the inner lumen of the access device. The delivery shaftincludes an interior lumen or aperture at its distal end for receivingthe patch and securing means in a collapsed configuration. The deliveryshaft further includes a means for deploying the patch and the securingmeans, which may comprise a rod slidably disposed in a lumen through thedelivery shaft. The rod includes means at its distal end for releasablycoupling to the patch, such as a threaded extension which couples to athreaded hub in the patch frame. The rod may be advanced distallyrelative to the delivery shaft to deploy the patch from the apertureinto the heart chamber on the side of the cardiac septum further awayfrom the point of introduction, e.g., the left atrium if the device hasbeen introduced into the heart through the right atrium. The patch ispositioned against the septum, and the securing means is deployed on theside of the cardiac septum opposite the patch, e.g., the right atrium inthe aforementioned case. The rod may then be decoupled from the patchand the delivery shaft is removed from the patient through the accessdevice.

[0018] Advantageously, the delivery shaft and deployment means areconfigured to allow the patch to be re-collapsed and repositioned if theposition of the patch is not satisfactory after initial deployment. Inone embodiment, the rod is drawn proximally relative to the deliveryshaft, whereby the patch is collapsed by engagement with the distal endof the delivery shaft. The patch securing means may be collapsed in asimilar manner, or by a separate mechanism. In an exemplary embodiment,one or more wires or sutures extend through a lumen in the deliveryshaft and are coupled to the securing means, e.g. to the outer ends ofthe spokes or struts of the securing means. By exerting tension on thewires, the securing means is drawn proximally into a collapsedconfiguration to allow it to be received in the aperture in the deliveryshaft. This allows the patch and securing means to be drawn back intothe aperture in the delivery shaft and redeployed at the desiredposition.

[0019] In an alternative embodiment, the septal defect closure meanscomprises a suturing device for applying at least one suture across theseptal defect. The suturing device includes a rigid delivery shaftsuitable for introduction through the inner lumen of the access device,and a plurality of needle holders mounted to the delivery shaft forreleasably holding at least two needles connected by a suture thread.The needle holders are movable between a contracted position suitablefor introducing the needles through the septal defect into the cardiacchamber on the opposite side of the septum, and an expanded position inwhich the tips of the needles are aimed proximally toward the cardiacseptum on opposing sides of the septal defect. In one embodiment, theneedle holders are mounted on opposing sides of a balloon which may bedeflated during introduction through a septal defect and then inflatedto move the needles into the expanded position. The needle holders arethen pulled proximally so that the needles penetrate the cardiac septum.A means is mounted to the delivery shaft for capturing the distal tipsof the needles after penetrating the septum. For example, the needlesmay have barbed tips which engage a porous fabric disk slidably mountedto the delivery shaft. The needle capture means is retracted to draw theneedles through the septum and out of the heart through the inner lumenof the access device. In this way, a plurality of sutures may be appliedto the cardiac septum simultaneously. Knots may then be tied in thesutures extracorporeally, and, using a long-handled endoscopicknot-pusher, pushed through the access device into the heart so as totighten the sutures and draw the opposing sides of the septal defecttogether.

[0020] In a further aspect of the invention, a method of accessing aninterior chamber of a beating heart is provided. According to the methodof the invention, a penetration is formed in a muscular wall of theheart into an interior chamber of the heart, and a distal end of atubular access device having an inner lumen is positioned through thepenetration. The penetration may be formed with various types ofendoscopic cutting devices, but, in a preferred embodiment, is formedwith the cutting means at the distal end of the obturator. which ispositioned in the inner lumen of the access device. This allows theaccess device to be introduced immediately upon forming the penetration,minimizing blood loss through the penetration. The method furtherincludes the step of forming a hemostasis seal between the access deviceand the penetration to inhibit blood loss through the penetration. Thisstep may include placing a purse string suture in the wall of the heartaround the penetration, inflating a balloon mounted to the access devicewithin the chamber of the heart, or radially-expanding a portion of theaccess device within the penetration.

[0021] The method also includes preventing blood flow out of the chamberof the heart through the inner lumen of the access device. This may beaccomplished by positioning the access device in a vertical orientationso that the pressure head of blood in the inner lumen is sufficient toprevent blood flow out of the heart, or a hemostasis valve may beprovided in the inner lumen.

[0022] While the method of accessing an interior chamber of the heartmay find use in open-chest surgical procedures, it is preferablyperformed using thoracoscopic techniques, wherein the ribs and sternumremain intact and are not significantly retracted during each step ofthe procedure. Using such techniques, a working space may be created inthe patient's chest cavity by collapsing one of the patient's lungs orusing jet ventilation techniques. A viewing scope such as an endoscopeor endoscopic surgical microscope may then be introduced through anintercostal space into the working space to view the exterior of theheart while the penetration is formed and the access device isintroduced. The viewing scope may include a video camera to provide avideo image of the heart for display on a monitor which can be viewedduring the procedure. Alternatively, the heart may be viewed directlythrough a lens on the viewing scope or through a trocar sleevepositioned in an intercostal space.

[0023] The method of accessing an interior chamber of the heartfacilitates the performance of a variety of intracardiac diagnostic andtreatment procedures. While it may be desirable to place the patient oncardiopulmonary bypass and arrest the heart during certain procedures,the invention facilitates the performance of a number of cardiacprocedures while the heart is beating, without the need forcardiopulmonary bypass or cardioplegic arrest, and with significantlyreduced risk of injury resulting from embolism.

[0024] In a further aspect of the invention, a method is provided forclosing a cardiac septal defect in a patient's heart. The patient isfirst placed under general anesthesia. The method is initiated bypositioning the distal end of the tubular access device in an interiorchamber of the heart and creating a hemostatic seal around the accessdevice, as described above. These steps are preferably performed undervisualization by means of an endoscope or other percutaneousvisualization device. One or more instruments are then passed throughthe inner lumen of the access device and out of the distal end thereof.The one or more instruments are then used to close the septal defect.

[0025] In a preferred embodiment, the method of the invention isperformed while the patient's ribs and sternum remain intact andunretracted, and while the patient's heart is beating. Access into thechest cavity is obtained through small percutaneous incisions orpunctures in the intercostal spaces between the ribs. Trocar sleeves,ports, or other types of percutaneous access cannulae may be placed inthese incisions or punctures to protect and retract surrounding tissueto facilitate introduction of instruments into the chest cavity.

[0026] Usually, the interior chamber of the heart will be the rightatrium, right ventricle, or left atrium, in which blood pressure islower than in the left ventricle. Preferably, the access device ispositioned in a vertical orientation, usually from a lateral side of thechest, with the distal end of the access device disposed in the interiorchamber. In this way, the static pressure head of blood within the innerlumen is equal to the pressure within the interior chamber, preventingthe flow of blood out of the interior chamber through the inner lumen.In an exemplary embodiment, small incisions and/or access ports areplaced in the third, fourth, fifth, or sixth intercostal spaces on alateral side of the chest. At least three such ports are usuallyrequired, one for introduction of the access device, one forintroduction of a visualization device such as an endoscope, and one forintroduction of other instruments for suturing, retraction, and otherpurposes.

[0027] Visualization within the interior of the heart may be provided byvarious means. Preferably, an ultrasonic probe is positioned in thepatient's esophagus, on the surface of the patient's chest, or in thechest cavity adjacent or in contact with the exterior of the heart toultrasonically image the interior of the heart. Alternatively, anendoscope with a translucent bulb or balloon over its distal end may beintroduced into the heart through the access device or through aseparate incision in the wall of the heart to allow video-based ordirect visualization of the interior of the heart. An angioscopeintroduced into the heart endovascularly through a peripheral vessel mayalso be used for intracardiac visualization. Fluoroscopy is anadditional technique for visualization.

[0028] The septal defect may be repaired in any of several ways. A patchmay be attached to the cardiac septum to cover the defect, or the defectmay be sutured closed. As described above, the patch may be anartificial biocompatible material, or it may be created out of a portionof the patient's pericardium or other natural membrane in the patient'sbody. The patch is introduced through the inner lumen of the accessdevice by means of a rigid delivery shaft to which the patch isdetachably coupled, allowing the patch to be positioned with a highdegree of control and precision. The patch is inserted through theseptal defect into the left side of the heart in a collapsedconfiguration, then expanded to cover the defect. When the patch hasbeen positioned across the defect, the interior of the heart isvisualized by ultrasonic imaging, fluoroscopy with contrast dyeinjection, or other means to determine whether the defect has beenclosed adequately. If not, the patch may be retrieved and repositionedwith the delivery shaft. Once positioned properly, the patch is anchoredto the cardiac septum, preferably by the compressive force of anopposing patch, frame or series of struts disposed on the right side ofthe septum. A number of pins or spikes may be provided on the patch topartially penetrate the septum to prevent migration. The patch is thenreleased from the delivery shaft.

[0029] In those embodiments in which the patch comprises a portion ofthe pericardium or other natural membrane, the invention allows theportion of membrane to be harvested from the patient's body and thenaffixed to a frame outside of the body cavity. Preferably, the membraneis harvested using instruments introduced percutaneously throughintercostal spaces, while keeping the ribs and sternum intact. Themembrane may be affixed to the frame using sutures, tissue adhesive,staples, or the like. Once the membrane is attached to the frame, thetwo may be coupled to the delivery shaft and introduced through theinner lumen of the access device into the heart for attachment to thecardiac septum.

[0030] Where the septal defect is to be closed by means of sutures, atleast two needles connected by a length of suture are introduced throughthe access device and inserted through the defect while the needles arein a radially retracted position. The needles are held in needle holderscoupled to the end of an delivery shaft. After insertion through thedefect, the needles are repositioned into a radially expanded positionin which they are further separated from one another. A balloon,expandable wire basket, scissors-type linkage, or camming device may beused for this purpose, or the needles may be held in needle holding rodshaving a shape memory so as to assume the radially expandedconfiguration when unrestrained. The needles are then drawn through thecardiac septum while in the expanded position. The needles are captured,and both ends of the length of suture are then tensioned to close thedefect. Usually the length of suture is long enough to allow the sutureneedles to be drawn outside of the body cavity through the inner lumenof the access device. Knots are then formed extracorporeally and pushedthrough the access device up to the cardiac septum using an endoscopicknot pusher. The sutures are trimmed using endoscopic scissors, and therepair is examined using one of the aforementioned visualizationtechniques.

[0031] Once the septal defect has been closed, the access device iswithdrawn from the penetration in the wall of the heart. If a balloon ora radially expanding portion of the access device has been utilized forhemostasis, it is first deflated or radially contracted. As the distalend of the access device is withdrawn, the purse string suture in theheart wall surrounding the access device is pulled tight, closing thepenetration. Knots are then formed in the purse string suture, eitherintracorporeally using endoscopic instruments, or extracorporeally,after which the knots are pushed into the body cavity and against theheart wall using an endoscopic knot pusher. Alternatively, thepenetration in the heart wall may be closed using endoscopic suturing orstapling techniques after the access device has been withdrawn. Allaccess ports are then withdrawn, percutaneous incisions and puncturesare closed, and the patient is recovered from anesthesia.

[0032] In a further aspect of the invention, devices and methods areprovided for performing electrophysiological procedures within theheart. Such procedures include electrophysiological cardiac mapping andablative treatment of cardiac arrhythmias, including ventricular andsupraventricular tachycardias and atrial fibrillation. The inventionprovides devices and methods for diagnosis and treatment of suchdiseases by accessing the interior of the heart through the intracardiacaccess device described above. Such techniques avoid the need for agross thoracotomy, and offer more control and precision in diagnosingand treating these diseases than are offered by intravascularelectrophysiological treatment techniques.

[0033] An electrophysiological device according to the inventioncomprises a rigid shaft suitable for introduction through the innerlumen of the access device. A deflectable tip is attached to the distalend of the shaft. The deflectable tip has at least one and usually aplurality of electrodes mounted to it. A steering means is provided inthe shaft for deflecting the tip into the desired orientation. Theelectrodes are electrically coupled to a connector at the proximal endof the shaft, which may be connected to a sensitive electrocardiogram(ECG) monitoring apparatus [radiofrequency generator?]. The deflectabletip may be introduced into a chamber of the heart through the accessdevice, and the electrodes positioned against a site on an interior wallof the heart to perform an electrophysiological procedure. For example,a plurality of electrode bands may be mounted in a spaced-apartrelationship on the deflectable tip, and the voltage difference can bemeasured across selected electrodes to identify aberrant conductionpathways in the heart wall, a process known as cardiac mapping. Inaddition, radiofrequency current may be delivered through one or moreelectrodes to ablate tissue at selected sites on the heart wall.

[0034] In a second embodiment, an electrophysiological device accordingto the invention comprises an expandable electrode array mounted to thedistal end of the rigid shaft. The electrode array includes a pluralityof electrodes mounted to an expandable support structure such as aframe, basket, balloon, or series of rods. The support structure iscoupled to an actuator at the proximal end of the shaft to facilitateselective deployment of the electrode array from a contractedconfiguration, in which it may be introduced through inner lumen of theaccess device, to an expanded configuration, in which the electrodes arespread apart into a two-dimensional or three-dimensional array. In oneembodiment, the electrode array is configured to conform generally tothe shape of an interior chamber of the heart in the expandedconfiguration. In this way, the electrodes may be positioned in apattern along the interior walls of the heart chamber to facilitatemapping or ablation of a large area without moving the device.

[0035] The electrophysiological devices of the invention areparticularly advantageous in that they offer a high degree of controland precision in positioning within the heart. Because the devices aremanipulated by means of a rigid shaft that spans only the relativelyshort distance from the interior of the heart to the exterior of thechest cavity, the electrodes can be easily and precisely positioned atmost locations within the heart chamber. Moreover, because theelectrophysiological devices are not introduced endovascularly, they arenot limited in size and configuration by blood vessel size. The devicesmay therefore have electrodes which are larger than those ofendovascular electrophysiology devices, permitting the delivery ofgreater amounts of energy to a tissue site. Further, the electrodes maybe greater in number and spread out over a larger area than endovascularelectrophysiology devices, allowing a greater area of a heart chamber tobe mapped or ablated without moving the device, thus increasing theprecision and efficiency of the procedure.

[0036] In a method of electrophysiological intervention according to theinvention, the tubular access device is introduced into a chamber of theheart in the manner described above. An electrophysiology deviceincluding at least one electrode coupled to the distal end of a shaft isintroduced through the tubular access device into the heart chamber. Theelectrode is positioned at a tissue site on a wall of the heart chamber,and either radiofrequency current is delivered to the tissue sitethrough the electrode, or electrical potential is sensed between two ormore selected electrodes. This technique may be used for either cardiacmapping or ablation of tissue. The method may further include deflectinga flexible tip attached to the shaft so that the electrode is positionedaway from a longitudinal axis of the shaft, permitting the electrode tobe positioned at various locations within the heart chamber.Alternatively, the method may include a step of expanding an electrodearray into an expanded configuration within the heart chamber. In theexpanded configuration, a plurality of electrodes of the electrode arrayare positioned in a two or three dimensional array which may bepositioned adjacent a treatment area on an interior wall of the heartchamber. Electrical potentials in the heart wall tissue may then besensed between selected electrodes, or radiofrequency current may bedelivered to the treatment area through one or more electrodes of theelectrode array.

[0037] The method may be performed in either the right side or the leftside of the heart, and in either the atria or the ventricles. Inventricular procedures, because it may be undesirable to form apenetration in the wall of a ventricle, the electrophysiology device maybe introduced through the access device into an atrium, from which it isadvanced through the tricuspid valve or mitral valve into the ventricle.Alternatively, the electrophysiology device may be positionedtranseptally through a puncture in the cardiac septum, wherein, afterelectrophysiological treatment is complete, the device is withdrawn andthe septal puncture closed.

[0038] The devices and methods of the invention may also be useful incombination with other types of cardiac treatment procedures. Forexample, the electrophysiology devices of the invention may be usefulfor mapping conduction pathways in the heart, which are then treated bymeans of thoracoscopic, endovascular, or open-chest techniques.Alternatively, thoracoscopic or endovascular techniques may be used formapping, and the intracardiac electrophysiological devices of theinvention may then be used for ablation or other treatments. In oneexemplary procedure, a thoracoscopic mapping device is introducedthrough an intercostal port in the chest for mapping cardiac conductionpathways on the exterior surface of the heart. The intracardiacelectrophysiology device of the invention is then utilized in theinterior of the heart to perform ablation, utilizing the mappinginformation generated on the exterior of the heart. Such a techniquecould be used for treatment of ventricular and supraventriculartachvcardias. Similarly, to treat atrial fibrillation, intracardiacmapping may be performed using the electrophysiology device of theinvention, and thoracoscopic or endovascular cutting or ablationinstruments may then be utilized through intercostal ports to perform aCox “maze”-type surgical transection of the atrium, whereby the mappinginformation is used to make precise incisions or ablation lines in themyocardium to create a directed conduction pathway between thesinoatrial node and the atrioventricular node.

[0039] By providing access to the interior of the heart withoutrequiring a gross thoracotomy and without the need to inducecardioplegic arrest, the invention enables a variety of intracardiacprocedures to be performed on a beating heart. In addition to septaldefect repair and the electrophysiological procedures described above,these procedures may include repair of other types of congenitaldefects, transmyocardial laser revascularization, mitral, aortic,pulmonary, or tricuspid valve inspection and repair, pulmonarythrombectomy, intracardiac inspection, removal of growths, myxomas,neoplasms, hypertrophic obstructive cardiopmyopathy and vegetations, andother diagnostic and treatment procedures.

[0040] The nature and advantages of the invention will become moreapparent from the following detailed description of the invention whentaken in conjunction with the accompanying exemplary drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0041]FIG. 1 is a perspective view of an intracardiac access deviceaccording to the invention.

[0042]FIG. 2 is a front partial cut-away view of a patient's heartshowing the intracardiac access device positioned through a wallthereof.

[0043] FIGS. 2A-2E are side views of a distal portion of theintracardiac access device of FIG. 1 showing various alternative typesof sealing means.

[0044] FIGS. 3A-3C are side, top, and end views, respectively, of theobturator of an intracardiac access device according to the inventionwith the cutting means retracted.

[0045] FIGS. 3D-3F are side, top, and end views, respectively, of theobturator of an intracardiac access device according to the inventionwith the cutting means extended.

[0046]FIG. 4 is a front cut-away view of a patient's chest showingcutting the pericardium to expose the heart according the method of theinvention.

[0047]FIG. 5 is a front cut-away view of a patient's chest showing theplacement of a purse-string suture in a muscular wall of the heartaccording to the method of the invention.

[0048]FIG. 6 is a front cut-away view of a patient's chest showing thepenetration of the muscular wall of the heart according the method ofthe invention.

[0049]FIG. 7 is a front cut-away view of a patient's chest showing theposition of the access device of FIG. 1 through the penetration in themuscular wall of the heart according to the method of the invention.

[0050]FIG. 8A is a front cut-away view of a patient's chest showing theposition of the access device of FIG. 1 through the penetration in themuscular wall of the heart with a balloon-type sealing means expandedaccording to the method of the invention.

[0051]FIG. 8B is a front cut-away view of a patient's chest showing theuse of an endoscope having a balloon over its distal end in a method ofvisualizing the interior of the heart according to the invention.

[0052]FIG. 9 is a front cut-away view of a patient's chest showing thedeployment of a distal patch of a septal defect repair device in achamber of the heart according to the method of the invention.

[0053]FIG. 10 is a side elevational view of a partially-deployed distalpatch of a septal defect repair device useful in the method of theinvention.

[0054] FIGS. 11A-11B are side cross-sectional and end views,respectively, of a hub of the distal patch of FIG. 10.

[0055]FIG. 12 is a side elevational view of a proximal patch of a septaldefect repair device useful in the method of the invention.

[0056] FIGS. 13A-13B are side cross-sectional and end views,respectively, of a hub of the proximal patch of FIG. 12.

[0057]FIG. 14 is a side cross-sectional view of the septal defect repairdevice of FIGS. 10-13 positioned in a lumen of a delivery shaftaccording to the method of the invention.

[0058]FIG. 15 is a front cut-away view of a patient's chest showing theexpansion of the distal patch of FIG. 10 in the left side of the heartaccording to the method of the invention.

[0059]FIG. 16 is a front cut-away view of a patient's chest showing thedeployment of the proximal patch of FIG. 12 in the right side of theheart according to the method of the invention.

[0060]FIG. 17 is a front cut-away view of a patient's chest showing theexpansion of the proximal patch of FIG. 12 in the right side of theheart according to the method of the invention.

[0061]FIG. 18 is a front cut-away view of a patient's chest showing theattachment of the proximal patch to the distal patch to repair theseptal defect according to the method of the invention.

[0062]FIG. 19 is a front cut-away view of a patient's chest showing theclosure of the penetration in the muscular wall of the heart accordingto the method of the invention.

[0063]FIG. 20 is a transverse cross-sectional view of the patient'schest showing an alternative technique for closing the penetration inthe muscular wall of the heart according to the method of the invention.

[0064]FIGS. 21A, 22A, and 23 are top partial cut-away views ofalternative embodiments of a septal defect repair device according tothe principles of the invention.

[0065]FIGS. 21B and 22B are side cross-sectional views of the septaldefect repair devices of FIGS. 21A and 22A, respectively.

[0066]FIG. 24A is a top partial cut-away view of a further embodiment ofa septal defect repair device according to the principles of theinvention.

[0067]FIG. 24B is a side partial cut-away view of the septal defectrepair device of FIG. 24A.

[0068]FIG. 25A is a side cut-away view of the septal defect repairdevice of FIGS. 24A-24B positioned in a collapsed configuration within adelivery shaft.

[0069]FIG. 25B is a side cut-away view of an actuator handle fordeployment of the septal defect repair device of FIGS. 24-24B.

[0070] FIGS. 26A-26B is a side cross-sectional view showing theattachment of the septal defect repair device of FIGS. 24A-24B to acardiac septum according to the method of the invention.

[0071] FIGS. 27 is a front cut-away view of a patient's chest showingthe introduction of a suturing device into the heart for repairing aseptal defect in an alternative embodiment of the method of theinvention.

[0072]FIG. 28 is a front cut-away view of a patient's chest showing theexpansion of a plurality of needles at the distal end of the suturingdevice according to the method of the invention.

[0073]FIG. 29A is a front cut-away view of a patient's chest showingdrawing the plurality of needles through the cardiac septum according tothe method of the invention.

[0074]FIG. 29B is a side view of the cardiac septum in the patient'schest of FIG. 29A showing the position of the needles through thecardiac septum according to the method of the invention.

[0075]FIG. 30A is a side view of the cardiac septum of FIG. 29B showingcapturing the needles in a capture disk according to the method of theinvention.

[0076]FIG. 30B is a side view of the cardiac septum of FIG. 30A showingwithdrawing the needles from the cardiac septum according to the methodof the invention.

[0077]FIG. 31A is a top view of the cardiac septum of FIG. 30A showingthe position of the sutures across the septal defect according to themethod of the invention.

[0078] FIGS. 31B-31C are perspective views of the cardiac septum of FIG.31A showing tensioning and tying the sutures to close the septal defectaccording to the method of the invention.

[0079] FIGS. 32A-32D are side views of an alternative embodiment of asuture-type septal defect repair device according to the invention,showing the deployment of the needles in the cardiac septum and thecapture of the needles according to the method of the invention.

[0080]FIG. 33 is a front cut-away view of a patient's chest showing anelectrophysiology device according to the invention positioned throughthe access device of FIG. 1 in a method of electrophysiologicaltreatment according to the invention.

[0081]FIG. 34 is a front cut-away view of a patient's chest showing analternative embodiment of an electrophysiology device according to theinvention positioned through the access device of FIG. 1 in a method ofelectrophysiological treatment according to the invention.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[0082] A first representative embodiment of an intracardiac accesssystem according to the invention is illustrated in FIG. 1. Theintracardiac access system 20 includes a tubular access device 22comprising a rigid shaft 24 having a distal end 26, a proximal end 28,and an inner lumen 30 extending therebetween. Access device 22 includesa means near distal end 26 for hemostatically sealing a cardiacpenetration through which shaft 24 is introduced, which may comprise atoroidal balloon 32. An inflation lumen 34 extends through shaft 24 andhas an opening 36 in communication with the interior of balloon 32. Aninflation fluid port 38 is mounted to shaft 24 at proximal end 28 incommunication with inflation lumen 34 and is configured for connectionto an inflation fluid delivery source such as a syringe or other ballooninflation device.

[0083] Access device 22 is configured to extend percutaneously throughan intercostal space and through a muscular wall of the heart withdistal end 26 positioned in an interior chamber of the heart andproximal end 28 positioned outside of the patient's chest cavity. In anexemplary embodiment, the tubular access device has a length of about 10to 30 cm, preferably about 25 cm, and an outer diameter of less thanabout 15 mm, and preferably about 5-10 mm. To allow introduction ofinstruments for visualization and surgical intervention within theheart, inner lumen 30 has a diameter of at least about 5 mm. Preferably,access device 22 is a rigid material such as stainless steel, titanium,or a rigid polymer, with a minimum durometer of about 75 Shore A.Alternatively, shaft 24 of access device 22 may be all or partiallyflexible with a minimum durometer of about 35 Shore A, and may alsoinclude pull wires or other means for steering or deflecting distal end26.

[0084] As illustrated in FIG. 2, distal end 26 of access device 22 isconfigured to be introduced through a penetration in cardiac wall 40 ofheart H. The hemostatic sealing means, e.g. balloon 32, functions toseal the penetration around the exterior of shaft 24 to prevent leakageof blood through the penetration from the interior of heart H. Asillustrated in FIGS. 2A-2E, a variety of hemostatic sealing means may beutilized. Balloon 32 may be mounted to shaft 24 spaced a short distancefrom distal end 26 so as to be positionable against the exterior surfaceof cardiac wall 40, as shown in FIG. 2A. Balloon 32 may alternatively bemounted close to distal end 26 so as to be positionable against theinterior surface of cardiac wall 40 as shown in FIG. 2B. In addition, apair of balloons 32, 42 may be mounted to shaft 24 spaced slightly apartto provide a seal on both sides of cardiac wall 40, as shown in FIG. 2C.

[0085] In a further alternative embodiment, not pictured, either or bothof balloons 32, 42 of FIG. 2C may be replaced by expanding mechanicalelements, such as moly-type fittings which are expanded undercompression exerted by, for example, sliding a slidable sleeve axiallyover shaft 24 which engages the proximal ends of the fittings.

[0086] In a further embodiment, shown in FIG. 2D, shaft 24 may have aflange 44 disposed at distal end 26, flange 44 having a proximal end 46with an outer diameter larger than that of shaft 24. When flange 44 isintroduced through a cardiac penetration, proximal end 46 of flange 44may be positioned so as to abut and seal against the interior surface ofcardiac wall 40. Flange 44 preferably has tapered side walls 48 tofacilitate introduction through the cardiac penetration. As shown inFIG. 2, balloon 32 may be mounted to shaft 24 spaced proximal to flange44 to compress cardiac wall 40 between the balloon and the flange andseal the cardiac penetration both interiorly and exteriorly.

[0087] In another embodiment, illustrated in FIG. 2E, shaft 24 has aradially-expanding portion 50 near distal end 26 which may beselectively expanded when distal end 26 has been positioned through thecardiac penetration. Exemplary radially-expanding dilators and cannulaehaving a construction suitable for application to the present inventionare disclosed in U.S. Pat. Nos. 5,183,464 and 4,921,479, which areincorporated herein by reference. A balloon 32 may also be mounted toshaft 24 distally of radially-expanding portion 50 to seal against theinterior surface of cardiac wall 40.

[0088] In each of the forementioned embodiments, it will frequently beadvantageous to place a purse string suture in cardiac wall 40 or applyanother means of gathering tissue around the cardiac penetration throughwhich shaft 24 is introduced to enhance hemostasis. The placement ofsuch a purse-string suture is described in detail below.

[0089] Referring now to FIGS. 3A-3C and 3D-3F, cardiac access system 20further includes an obturator 52 removably positionable in inner lumen30. Obturator 52 comprises a tubular shaft 54 having a distal end 56, aproximal end 58, and an axial lumen 59. Distal end 56 is conical inshape and has a transverse slot 57 in communication with axial lumen 59.A cutting means 60 for forming a penetration in a heart wall is slidablyreceived within slot 57, and, in an exemplary embodiment, comprises astainless steel blade 62 having a sharpened distal edge 64 tapering to apoint 66. Blade 62 is coupled to a linkage 72 slidably disposed in axiallumen 59. A handle 74 is mounted to proximal end 58 of shaft 54, and asliding actuator 76 is mounted to handle 74. Linkage 72 is coupled toactuator 76, so that actuator 76 may be used to slide blade 62 distallyto expose edge 64 and point 66. A compression spring 78 is disposedwithin an aperture in handle 74 and engages a collar 79 on linkage 72 tobias blade 62 proximally so that it is protected within slot 57.

[0090] Actuator 76 may be configured to lock in a distal position inwhich blade 62 is fully exposed, in a proximal position in which blade62 is fully exposed, or in any other position between the two. In anexemplary configuration, actuator 76 comprises a button 77 having anupper portion 81 of smaller diameter which is slidable within a channel80 in handle 74, and having a lower portion 82 of larger diameterdesigned to seat within a detent 84 at the proximal end of channel 80.Button 77 is biased upward by a spring 85 to automatically lock intodetent 84 when aligned therewith. In this way, blade 62 is locked in theproximal position and is unlikely to be inadvertently exposed by theuser. When exposure of blade 62 is desired, button 77 is pushed downwardand distally. Release of pressure on button 77 causes blade 62 toretract automatically.

[0091] The length of shaft 54 is selected so that when obturator 52 isdisposed within inner lumen 30, cutting means 60 extends distally ofdistal end 26 of access device 22 and handle 74 is near or againstproximal end 28 of access device 22. In this way, blade 62 may be usedto create a penetration in the heart wall while obturator 52 ispositioned within access device 22, allowing access device 22 to beintroduced through the heart wall as or immediately after thepenetration is formed, thereby minimizing blood loss through thepenetration. Once access device 22 is introduced through the cardiacpenetration, obturator 52 is withdrawn from inner lumen 30.

[0092] As will be described more fully below, access device 22 isusually introduced into the right atrium, right ventricle, or leftatrium in a vertical or near-vertical orientation so that blood flow outof the heart through inner lumen 30 is prevented by gravity—i.e., thepressure head of blood in inner lumen 30 is equal to that in the cardiacchamber. In such cases, there is no need for a hemostasis valve withininner lumen 30. However, in cases in which access device 22 is to beintroduced into the higher pressure chamber such as the left ventricle,or in which access device 22 is to be positioned in an orientation inwhich blood might flow through inner lumen 30, a hemostasis valve (notshown) may be provided within inner lumen 30. The hemostasis valve maybe positioned at the proximal end, the distal end, or a mid-positionwithin inner lumen 30, and will be configured to allow instruments to beintroduced through inner lumen 30 with minimal blood loss. Suitablehemostasis valves are described, for example, in U.S. Pat. Nos.4,000,739, 4,436,519, 5,154,701, 4,946,133, 5,000,745, 4,177,814, and5,300,033, which are incorporated herein by reference.

[0093] A method of accessing the interior of the heart according to theinvention will now be described with reference to FIGS. 4-8. The methodwill be described in relation to accessing a left or right atrium of theheart from the right side of the chest, but it should be understood thatthe principles described will be equally applicable to accessing theleft or right ventricle and using any of a variety of approaches.

[0094] The patient is prepared for cardiac surgery in the conventionalmanner, and general anesthesia is induced. The patient is positioned onthe patient's left side so that the right lateral side of the chest isdisposed upward. Two to three small incisions 2-3 cm in length are madebetween the ribs, usually in the third, fourth, or fifth intercostalspaces. Thoracoscopic access ports 90 (e.g. trocar sleeves or othertubular cannulae), are positioned in each incision to retract awayadjacent tissue and protect it from trauma as instruments are introducedinto the chest cavity. Access ports 90 have an outer diameter which doesnot require retraction, cutting or removal of ribs, preferably less than14 mm, and an axial passage with a diameter less than about 12 mm.Access ports 90 may also be non-circular in cross-section, or may bemade of a flexible material to deform into a non-circular shape whenintroduced between two ribs. The right lung is deflated usingconventional techniques, usually by introducing a tube through thepatient's trachea into the right lung and applying a vacuum through thetube to deflate the lung. An endoscopic visualization device such as athoracoscope 92 connected to a video monitor (not shown) by a cable 93is introduced through one of access ports 90 to visualize the interiorof the chest cavity. Atraumatic retraction instruments may be introducedthrough access ports 90 to assist in deflating and retracting the lung,thereby providing a working space within the chest cavity.

[0095] Referring to FIG. 4, in order to gain access to the heart, anopening is made in the pericardium 94 using thoracoscopic instrumentsintroduced through access ports 90, including thoracoscopic scissors 96and thoracoscopic forceps 98. Instruments suitable for use in thisprocedure are described in copending application Ser. No. 08/194,946,filed Feb. 11, 1994, which is incorporated herein by reference. Anopening approximately 2 cm-8 cm square is formed in the pericardium,exposing the exterior of the heart 100.

[0096] As shown in FIG. 5, a purse string suture 102 is then placed inthe wall 104 of heart 100 around the site at which it is desired tointroduce access device 22. This is accomplished by using thoracoscopicneedle drivers 106 to introduce into the chest cavity a curved sutureneedle 108 attached to one end of a suture thread 110, and to drive theneedle through the heart wall to form a running stitch in a circularpattern approximately 12-14 mm in diameter. A double-armed suture mayalso be used, wherein the suture thread 110 has needles at both ends,allowing each needle to be used to form one semi-circular portion of thepurse-string. Suture thread 110 may be long enough to allow both ends ofthe suture to be drawn outside of the chest cavity once purse-stringsuture 102 has been placed, or it may be shorter and manipulated withinthe chest cavity using thoracoscopic instruments. Suture needle 108 isthen cut from thread 110 using thoracoscopic scissors.

[0097] Access device 22 may now be introduced into heart 100. In somecases, it may be advantageous to first place the patient oncardiopulmonary bypass and to place the heart under cardioplegic arrestbefore introducing access device 22. Preferably, however, heart 100remains beating during the procedure to avoid the trauma and risksassociated with cardioplegic arrest. Obturator 52 is positioned withininner lumen 30 of access device 22 so that distal end 56 of theobturator is exposed distally of distal end 26 of the access device.Access device 22 with obturator 52 positioned therein is introducedthrough an access port 90 into the chest cavity, and distal end 56 ofthe obturator is positioned against heart wall 104 centrally within thebounds of purse-string suture 102. Button 77 on handle 94 of theobturator is then pressed downward and distally so as to extend blade 62from distal end 56, causing blade 62 to penetrate through heart wall104. A thoracoscopic grasping instrument (not shown) may be used tograsp the heart wall near purse string suture 102 to counter theinsertion force of blade 62 and access device 22. As blade 62 penetratesthe heart wall, access device 22 is advanced distally in conjunctionwith obturator 52 so that both devices extend into the heart through thepenetration 114 formed in heart wall 104.

[0098] Once distal end 26 of access device 22, including balloon 32 orflange 44 if used, is within the interior of heart 100, purse-stringsuture 102 is cinched tightly to form a hemostatic seal around accessdevice 22, as shown in FIG. 7. One or a pair of thoracoscopic cinchingdevices 116 may be used for this purpose. Each cinching device 116comprises a shaft 118 with a slidable hook 120 at its distal end whichcan be used to grasp a loop of purse-string suture 102. Hook 120 mayretracted proximally to frictionally retain suture thread 110 againstthe distal end of shaft 118. Loops on opposing sides of purse-stringsuture 102 may be grasped in this manner, and cinching devices 116 thenwithdrawn proximally to cinch purse-string suture 102 tightly, therebygathering heart wall tissue against the exterior of access cannula 22 toform a hemostatic seal. Cinching devices 116 may be clamped in positionto maintain tension on suture thread 110. Alternatively, a slidablesleeve 122 may be provided around shaft 118. Once a suture loop has beensecured in hook 120, slidable sleeve 122 may be slid distally relativeto shaft 118 until it abuts against the surface of heart wall 104. Shaft118 is then pulled proximally relative to sleeve 122 to obtain thedesired degree of tension on suture thread 110. Sleeve 122 is configuredto frictionally retain shaft 118 in position to maintain tension on thesuture.

[0099] If a balloon or radially-expanding portion of access device 22 isused to enhance hemostasis, it is now activated. The use of a balloon32, described above in reference to FIG. 2B, is illustrated in FIG. 8A.Once distal end 26 of access device 22 is introduced into the interiorof heart 100, balloon 32 is inflated by introducing an inflation fluidsuch as saline through inflation lumen 34 (FIG. 1). A syringe or othercommercially-available inflation device connected to inflation port 38may be used for this purpose.

[0100] Obturator 52 is then withdrawn from inner lumen 30 of accessdevice 22. As described above, access device 22 is preferably positionedin a vertical orientation so that outflow of blood from the heartthrough inner lumen 30 is prevented by gravity—that is, the pressurehead of blood within inner lumen 30 is equal to that in the cardiacchamber. In other cases, a hemostasis valve (not shown) is providedwithin inner lumen 30 to prevent blood flow from the heart, whileallowing instruments to be introduced through the access device.

[0101] The patient has now been prepared for a diagnostic or treatmentprocedure to be carried out within heart 100 through access device 22.Advantageously, the need for gross thoracotomy, cardiopulmonary bypassand cardioplegic arrest have been avoided, while providing a relativelylarge, straight, and hemostatically-sealed access passage directly intothe interior of the heart.

[0102] Visualization within the heart may be accomplished in any ofseveral ways. Transesophageal echocardiography may be used, wherein anultrasonic probe is placed in the patient's esophagus or stomach toultrasonically image the interior of the heart. An ultrasonic probe mayalso be placed through one of access ports 90 into the chest cavity andadjacent the exterior of the heart for ultrasonically imaging theinterior of the heart.

[0103] Alternatively, as illustrated in FIG. 8B, an endoscope 121 havingan optically transparent bulb such as an inflatable balloon 123 over itsdistal end 125 may be introduced through access device 22 into theinterior of the heart. Balloon 123 may be inflated with a transparentinflation fluid such as saline to displace blood away from distal end125 and may be positioned against a site such as septal defect D inseptum S, allowing the location, shape, and size of defect D to bevisualized. In one embodiment, endoscope 121 is a conventional,commercially-available endoscope such as a V. Mueller Model No. LA 7005(V. Mueller, Inc, Deerfield, Ill.), having a tubular shaft 127 in whichone or more lenses (not shown) are mounted, an eyepiece 129 at itsproximal end for looking through tubular shaft 127, and a connector 131for connection to a light source which transmits light through opticalfibers (not shown) extending through tubular shaft 127 to distal end125. Endoscope 121 is slidably positioned in an outer sleeve 133 havinga distal end 135 to which balloon 123 is attached. Outer sleeve 133 hasa luer connection 137 on its proximal end in communication with aninflation lumen (not shown) extending through outer sleeve 133 to anoutlet port 139 at distal end 135 within the interior of balloon 123.Luer connection 137 is adapted for connection to a syringe 141 forinjecting a transparent inflation fluid such as saline into balloon 123for inflation thereof. A tubular, compliant seal 143 is attached to aproximal end of outer sleeve 133 to provide a fluid-tight seal betweenendoscope 121 and outer sleeve 133. It will be understood to those ofskill in the art that, instead of using separate outer sleeve 133,balloon 123 could be mounted directly to distal end 125 of endoscope 121and an inflation lumen provided in shaft 127 for inflation of theballoon.

[0104] In use, endoscope 121 is positioned in outer sleeve 133 outsideof the patient, and the two are together introduced through inner lumen30 of access device 22 with balloon 123 evacuated of fluid in acollapsed configuration. Once balloon 123 is within the heart, saline isinjected into balloon 123 to inflate the balloon to a diameter ofapproximately 2-6 cm. Balloon 123 is then positioned against the site tobe visualized, e.g., septum S around defect D. The size and location ofthe defect D may then be visualized by looking through eyepiece 129.Additionally, endoscope 121 may include a video camera mount to allowvideo imaging and remote viewing of the interior of the heart on a videomonitor.

[0105] Instead of a balloon or bulb over distal end 125, saline may beinjected under pressure through a lumen in endoscope 121 or in outersleeve 131 and out of a port at or near distal end 125 to displace bloodaway from the distal end to provide a transparent field of view.

[0106] As a further visualization alternative, an endoscope may beutilized which employs a specialized light filter, so that only thosewavelengths of light not absorbed by blood are transmitted into theheart. The endoscope utilizes a CCD chip designed to receive and reactto such light wavelengths and transmit the image received to a videomonitor. In this way, the endoscope can be positioned in the heartthrough access device 22 and used to see through blood to observe aregion of the heart. A visualization system based on such principles isdescribed in U.S. Pat. No. 4,786,155, which is incorporated herein byreference.

[0107] In still another alternative for visualization, particularlyuseful in imaging an atrial or ventricular septal defect, a verysmall-profile light source such as an optical fiber is positioned in theleft atrium or left ventricle, opposite the right atrium or rightventricle in which access device 22 is positioned. The light source maybe introduced through access device 22 and through the septal defectinto the left side of the heart, or it may be introduced through aminute puncture in the left side of the heart. The puncture may beclosed by a purse-string suture if needed. An endoscope is thenpositioned through access device 22 into the right side of the heartopposite the light source. The endoscope utilizes a CCD chip designed toreceive and react to those light wavelengths transmitted through blood,as well as any light wavelengths transmitted through the interatrial orinterventricular septum. This produces a shadow-like image of the septaldefect, which is received by the CCD and displayed on a video monitor,thereby imaging the size, shape and location of the septal defect.

[0108] With access device 22 in position in the heart and a means ofvisualization in place, a number of intracardiac procedures may beperformed. One such procedure is the repair of atrial septal defects,which will now be described with reference to FIGS. 9-32.

[0109] FIGS. 9-20 illustrate an exemplary embodiment of a system andmethod for repairing an atrial septal defect according to the invention.In these Figures, an umbrella-type septal defect repair patch is shownwhich is similar to that that described in U.S. Pat. No. 3,874,388 toKing, which is incorporated herein by reference. It should beunderstood, however, that any of a number of different septal defectrepair patches may be utilized in conjunction with the system and methodof the invention without departing from the principles hereof. Some ofthe septal defect repair patches which could be utilized are described,for example, in U.S. Pat. Nos. 4,007,743, 5,334,217, 4,917,089,5,284,488, and 5,108,420, which are incorporated herein by reference.Another septal defect repair patch which could be used with the presentinvention is disclosed in PCT application No. PCT/US92/10141 to Pavcnik,published Jun. 10, 1993.

[0110] As shown in FIG. 9, the septal defect repair system of theinvention includes, in addition to access device 22 described above, adefect repair device 130 and a delivery means 132. Defect repair device130 comprises, in this embodiment, a double umbrella-type patch similarto that described in the '388 patent to King. Delivery means 132comprises a tubular delivery shaft 134 having a distal end 136positionable through inner lumen 30 of access device 22, and a proximalend (not illustrated in FIG. 9) which is used to manipulate deliverymeans 132 from outside of the chest cavity. An outer tubular control rod138 is slidably disposed within delivery shaft 134, and an inner controlrod 140 is slidably disposed within outer control rod 138. Inner controlrod 140 has a distal end 142 detachably coupled to a distal patch 144 ofdefect repair device 130.

[0111] Preferably, delivery shaft 134 is generally straight and rigid tofacilitate introduction through access device 22 and manipulation ofdelivery means 132 from its proximal end. Delivery shaft 134 is thusstainless steel, titanium, another biocompatible metal, or abiocompatible polymer with a minimum durometer of 75 Shore A. Outercontrol rod 138 and inner control rod 140 are preferably also a rigidmaterial such as stainless steel or titanium, although some flexibilitymay be tolerated in these members since they are supported exteriorly bydelivery shaft 134, so long as the inner and outer control rods havesufficient column strength to perform their respective functions, asdescribed below.

[0112] The details of an exemplary embodiment of defect repair device130 are illustrated in FIGS. 11, 12A-12B, 13 and 14A-14B, which show adouble-umbrella device similar to that disclosed in the King patent.FIG. 11 illustrates distal patch 144, which includes a central hub 146to which a plurality, e.g. six, radially-extending struts 148 arecoupled. Hub 146 and struts 148 are a rigid material such as stainlesssteel or a biocompatible polymer. Struts 148 include sharpened points149 pointing generally perpendicular to the struts at their outer endsfor penetrating the cardiac septum. A biocompatible flexible fabric 150of a polyester such as Dacron™, an expanded polytetrafluoroethylene suchas Gore-Tex® (W. L. Gore and Assoc., Inc.), silk, nylon, silastic, aportion of the patient's pericardium, or other biocompatible flexiblematerial impervious to blood is attached to hub 146 by a keeper 152 andto struts 148 by sutures 154.

[0113] As shown in FIGS. 11A-11B, struts 148 may be hingedly coupled tohub 146 by means of a hinge ring 156 which extends through an eyelet 158at the end of each strut. Hinge ring 156 and struts 148 are retained onhub 146 by keeper 152. Alternatively, struts 148 may be a resilient,flexible material and rigidly coupled to hub 146 so as, to naturallyassume a radially expanded configuration when unrestrained. A pluralityof axial grooves 159 are provided on hub 146 to receive struts 148 whencollapsed inward. Hub 146 further includes a threaded hole 160 on itsproximal end into which the threaded distal end of inner control rod 140may be threaded. A circumferential flange 162 is disposed about theproximal end of hub 146 for attachment to the proximal patch of thedefect repair device, as described below.

[0114] Referring to FIGS. 12 and 13A-13B, defect repair device 130further includes a proximal patch 164 having a construction much likedistal patch 144. A plurality of struts 166 are hingedly coupled to acentral hub 168 by means of a hinge ring 170 extending through eyelets172 in the inner ends of the struts. Each strut 166 has an inwardlyextending point 174 at its outer end for engaging the cardiac septum. Aflexible fabric membrane 176 is attached to hub 168 by a keeper 180 andto struts 166 by sutures 182. Additional suture loops 184 are attachedto struts 166 to allow attachment of tie wires for deployment ofproximal patch 164, as described below.

[0115] As shown in FIGS. 13A-13B, hub 168 has a plurality of axialgrooves 186 for receiving struts 166 in a collapsed configuration. Hub168 also has an axial passage 188 of sufficient diameter to allow innercontrol rod 140 to extend slidably through it with minimal friction. Onits distal end, hub 168 has a cavity 190 having an annular groove 192for receiving circumferential flange 162 of hub 146 in a snap-fitrelationship.

[0116] Referring to FIG. 14, during introduction through access device22, distal patch 144 and proximal patch 64 are preferably positioned ina collapsed configuration within delivery shaft 134 near distal end 136.Inner control rod 140 is positioned slidably through outer control rod138, through axial passage 188 in hub 168 of proximal patch 164, andthreaded into hole 160 in distal patch 144. Tie wires 194 are attachedto suture loops 184 and extend proximally through delivery shaft 134 outof the chest cavity. As shown in FIG. 9, delivery shaft 134 isintroduced through the right atrium RA and into the left atrium LAthrough septal defect D. Inner control rod 140 is then advanced distallyrelative to delivery shaft 134 to deploy distal patch 144 out ofdelivery shaft 134 into left atrium LA.

[0117] As illustrated in FIG. 15, with distal patch 144 deployed in theleft atrium, inner control rod 140 is pulled proximally relative todelivery shaft 134 until distal end 136 of the delivery shaft engagesstruts 148 (not shown in FIG. 15), urging struts 148 outward to aradially expanded position in which distal patch 144 is generallydisk-shaped and parallel to cardiac septum S. Delivery shaft 134 andcontrol rod 140 are then pulled proximally in the direction of arrow A1until distal patch 144 engages septum S and points 149 of struts 148partially penetrate septum S. This is done under visualization by TEE orone of the other techniques described above in order to ensure properpositioning of distal patch 144 so as to fully block blood flow acrossdefect D. If, after initial placement, shunting of blood is detectedacross the defect, distal patch 144 may be repositioned by advancingdelivery shaft 134 distally to disengage patch 144 from septum S, thenmanipulating delivery shaft 134 to position distal patch 144 in thedesired location. The straightness, rigidity, and relatively shortlength of delivery shaft 134 provide the user a high degree of controland precision in placing the patch in the best possible position onseptum S.

[0118] In some cases it may desirable to have the capacity tore-collapse distal patch 144 and replace it within delivery shaft 134for repositioning or removal from the patient. In such cases, tie wiresmay be provided which are coupled to the inner sides of struts 148 andextend through delivery shaft 134 out of the chest cavity. By tensioningthe tie wires, struts 148 may be urged back into a collapsed positionand distal patch 144 then pulled back into delivery shaft 134.

[0119] With distal patch 144 anchored in septum S, proximal patch 164 isnext deployed in the right atrium RA, as illustrated in FIG. 16. This isaccomplished by pulling delivery shaft 134 proximally to provide somespace between its distal end 136 and septum S. Outer control rod 138 isthen advanced distally relative to delivery shaft 134 to deploy proximalpatch 164 out of delivery shaft 134 in the direction of arrow A2.Proximal patch 164 and outer control rod 138 slide relative to innercontrol rod 140, which is maintained in tension to keep distal patch 144against septum S.

[0120] As shown in FIG. 17, tie wires 194 are then tensioned so as tourge struts 166 outward into a radially expanded position in whichproximal patch 164 is generally disk-shaped and parallel to septum S. Asillustrated in FIG. 18, outer control rod 138 and proximal patch 164 arethen advanced distally over inner control rod 140 until hub 168 of theproximal patch engages and snaps into hub 146 of distal patch 144.Points 174 on the ends of struts 166 partially penetrate septum S toanchor the patch in position. Tie lines 194 are removed from proximalpatch 164, by, for example, cutting the tie lines with a cuttinginstrument introduced through access device 22 after removal of deliveryshaft 134. Alternatively, tie lines 194 may be looped through sutureloops 184 on proximal patch 164 so that both ends extend out of thechest cavity, in which case one end of each tie line is simply pulledthrough the suture loop to remove the tie line.

[0121] It will be understood to those of ordinary skill in the art thata variety of different types of actuators of well-known construction maybe employed at the proximal end of delivery means 132 to allow the userto selectively deploy defect repair device 130 in the heart. In oneembodiment, not pictured, a handle is fixed to the proximal end ofdelivery shaft 134 which is suitable for being grasped in the user'shand. A pair of slidable buttons are mounted to the handle, one beingcoupled to the proximal end of the inner control rod 140 and the secondbeing coupled to the proximal end of outer control rod 138. In this way,the user can independently deploy distal patch 144 and proximal patch164 by sliding the respective buttons on the handle. A passage is alsoprovided in the handle in communication with the interior of deliveryshaft 134 to allow tie wires 194 to extend out of the delivery shaftoutside of the patient's body.

[0122] Delivery shaft 134, along with inner control rod 140 and outercontrol rod 138, are then removed from the chest cavity through accessdevice 22. If desired, the defect repair may be inspected by placing anendoscope with a transparent bulb or balloon over its distal end throughaccess device 22 into right atrium RA. The bulb or balloon is positionedagainst septum S and/or proximal patch 164 to inspect the position ofthe patch and to determine whether the septal defect has been completelyoccluded. Shunting of blood may also be detected using TEE or otherultrasonic technique. If patch position is satisfactory, access device22 may be removed from the patient. Balloon 32 (if used) is deflated,and access device 22 is withdrawn from the penetration in heart wall104. As shown in FIG. 19, sutures 110 are pulled tight as access device22 is withdrawn to close the penetration without significant loss ofblood from the heart. Knots are tied in sutures 110, usuallyextracorporeally, and slid into the chest cavity and against heart wall104 using an endoscopic knot pusher 196 introduced through access port90. This may be done under visualization with an endoscope introducedthrough a separate access port 90 (not shown in FIG. 19). Sutures 110are then trimmed off with a pair of endoscopic scissors.

[0123] An alternative method of closing the penetration in the heartwall is illustrated in FIG. 20. In this technique, an endoscopic stapleapplier is used to apply one or more staples to the heart wall acrossthe penetration. A staple applier such as, for example, an AutoSuture™Powered Multifire Endo TA60 device available from United States SurgicalCorp. of Norwalk, Conn., may be utilized. Under visualization using anendoscope positioned in an access port 90, stapler 198 is introducedthrough an access port 200 in the anterior wall of the patient's chestso that the anvils 202 are generally parallel to heart wall 104. Theheart wall around the penetration is pursed up using endoscopic forcepsso that anvils 202 can be positioned around a portion of the myocardiumthat includes the penetration. The stapler is then actuated, applying arow of staples through the heart wall across the penetration to seal itclosed.

[0124] With the penetration in heart wall 104 closed, the procedure iscompleted by removing all access ports 90 and closing all percutaneousincisions. The right lung is reinflated, the endotracheal tube isremoved, and the patient is recovered from anesthesia.

[0125] Additional embodiments of defect repair device 130 of theinvention are illustrated in FIGS. 21A-21B, 22A-22B, 23, and 24A-24B.Defect repair devices 130A, 130B, 130C of FIGS. 21-23 each include adistal patch 206, 208, 210, and a proximal patch 212, 214, 216. Thepatches are a flexible, biocompatible, and blood impervious material,preferably conducive to endothelialization after implantation. Suitablematerials include polyester mesh, knit fabrics of expandedpolytetrafluoroethylene treated for low porosity, absorbablepolyhydroxybutyrate, autologous pericardium, bovine or porcinepericardium, polyurethane and polypropylene mesh. The proximal anddistal patches are attached together in a parallel relationship by anattachment means 218, 220, 222 forming a ring at the center of thepatches. Attachment means 218 may comprise a single suture in a circularrunning stitch, a plurality of individual knotted suture loops, rivets,or other fasteners, or a circular series or continuous line of adhesivebonding or heat welding. A wire support frame 224, 226, 228 is attachedaround the outer edges of the distal and proximal patches, preferably byfolding the outer edges of the patch around the frame and suturing orbonding the patch to itself, thereby enclosing the support frame withinthe patch material. On each patch, support frame 224. 226, 228 ispreferably a single continuous wire of Nitinol™, a superelasticnickel-titanium alloy available from Raychem Corporation, titanium, orstainless steel. Support frame 224. 226, 228 includes a plurality ofloops 230, 232, 234 formed in the plane of each patch to allow forlongitudinal flexing and bending of the frame to facilitate collapsingthe patches during introduction. The loops may be formed outwardly tolie outside of the periphery of each side of the frame as illustrated inFIG. 21A, or inwardly to lie within the periphery of the frame asillustrated in FIGS. 22 and 23.

[0126] In the embodiment of FIGS. 22A-22B, defect repair device 130Bincludes a central hub 236 attached to distal and proximal patches 208,214. Hub 236 has a post 238 extending through patches 208, 214, and aretainer 240 threaded or press-fit onto the distal end of post 238,thereby fixing hub 236 to the patches. Hub 236 also has a threaded hole242 in its proximal end to which an introducer shaft may be threadablycoupled. By allowing defect repair device 130 to be coupled to anintroducer shaft via hub 236, the user is given a higher degree ofcontrol in positioning and repositioning the patch, as described morefully below. It should be understood that any of the embodiments inFIGS. 21A-21B and 23 may be provided with a hub like hub 236 of FIG. 22.

[0127] Patches 212, 214, 216 may have any of a variety of shapesincluding square or rectangular (FIGS. 21 and 22), hexagonal (FIG. 23),triangular, octagonal, pentagonal, circular, oval, or other shape. Adefect repair device like those disclosed in U.S. Pat. No. 5,334,217 toDas, which is incorporated herein by reference, may also be utilized inconjunction with the present invention.

[0128] FIGS. 24A-24B illustrate still another embodiment of defectrepair device 130. In this embodiment, defect repair device 130D has adistal patch 244 of a flexible, biocompatible material attached to awire frame 246, much like distal patches 206, 208, 210 of FIGS. 21-23.Wire frame 246 may be continuous wire of stainless steel, Nitinol™, orother biocompatible, resilient metal or polymer, and may include aplurality of loops 248 like those shown in FIGS. 21-23. Rather thanbeing attached to a proximal patch like the above-described embodiments,however, distal patch 244 of FIG. 24 is attached to a central hub 250,to which are coupled a plurality of radially-extending struts 252 on theproximal side of patch 244 and parallel thereto. While defect repairdevice 130D is pictured with four such struts in FIGS. 24A-24B, struts252 may be between three and twelve in number. Struts 252 are Nitinol,stainless steel, or other flexible, resilient biocompatible metal orpolymer, and are coupled to hub 250 in such a way that the outer ends254 of struts 252 are biased toward patch 244 and deflectable away frompatch 244 about an axis perpendicular to the central axis of hub 250. Anadditional patch (not shown) may be attached to struts 252 to providepatches on both sides of septum S, although in most cases, a singlepatch on the higher pressure side of the septum (the left side of theheart) is sufficient to prevent interatrial or interventricular bloodflow through a septal defect.

[0129] In the embodiment shown, the inner ends 256 of struts 252 areformed in a loop which acts as a torsion spring to bias the strutstoward patch 244. Alternatively, inner ends 256 may be straight andanchored directly to hub 250, wherein each strut 252 acts as a leafspring biased toward patch 244. Optionally, distal struts 260 coupled tohub 250 may be provided adjacent to or attached to patch 244, distallyand parallel to struts 252, so as to compressively engage septum Sbetween the two sets of struts, as shown in FIG. 24B. In the embodimentshown, each of struts 252 is formed with one of distal struts 260 from asingle continuous length of wire, with a first loop at the inner end 256of each strut 252, and a second loop at the inner end 262 of each distalstrut 260. A retainer 261, which may be a snap-ring, band, or loop ofsuture, retains struts 252 and distal struts 260 on hub 250. Struts 252,260 may be round in cross-section, or rectangular so as to increase themoment of inertia in the transverse direction so that the struts tend tobend only about an axis perpendicular to the central axis of hub 250.Outer ends 254, 264 of struts 252 and distal struts 260 may include asharp point 258 oriented generally perpendicular to the straight portionof the strut so as to partially penetrate septum S, as shown in FIG.24B. Points 258 may alternatively be made long enough so that the pointscompletely penetrate septum S, allowing visual inspection of strutdeployment by observing emergence of each point on the opposite side ofthe septum. In one embodiment, outer ends 254 are formed in a 270° loopso that points 258 attain a perpendicular orientation. Hub 250 includesa threaded hole 266 which may be coupled to an introducer shaft.

[0130] Defect repair device 130D of FIG. 24A is shown in FIG. 25A in acollapsed configuration within delivery shaft 134 for introduction intothe heart through access device 22. Hub 250 is threadably mounted to arod 273 attached to the end of an elongated tubular introducer shaft 268to facilitate deployment of repair device 130D within the heart. Patch244 and distal struts 260 are collapsed together distally of hub 250,while struts 252 are collapsed together proximally of hub 250. Springloops at the inner ends 256, 262 of struts 252, 260 bias the strutsoutwardly against the inner wall of delivery shaft 134. A retractionwire 270, which may be a length of suture or wire, is attached to theouter end 254 of each strut 252 and extend through the interior ofintroducer shaft 268. After deployment of repair device 130D, retractionwires 270 may by used to retract the device back into delivery shaft 134to reposition or remove the device. By tensioning retraction wires 270from outside of the patient's body, struts 252 are re-collapsed andrepair device 130 may be pulled back into delivery shaft 134.Preferably, retraction wires 270 are looped through outer ends 254 ofthe struts so that both ends of the retraction wires extend out of thebody through delivery shaft 134. In this way, once repair device 130D isdeployed satisfactorily, retraction wires 270 may be removed by simplypulling one end. Short lengths of suture or wire (not shown) may also beconnected between outer ends 254 of adjacent pairs of struts 252, and aretraction wire 270 then looped through each short length. Thisconfiguration helps to maintain spacing between struts 252 and preventtangling. Alternatively, a single retraction wire may extend through allof the loops at the outer ends of struts 252, with both ends of thesingle retraction wire extending out of the patient's body throughdelivery shaft 134.

[0131]FIG. 25B illustrates an exemplary embodiment of an actuator handle249 mounted to a proximal end of delivery shaft 134 for deploying repairdevice 130D. Delivery shaft 134 is slidably received within an axialbore 251 in a distal end of actuator handle 249. An actuator button 253is slidably mounted to a post 255 attached to a proximal end of deliveryshaft 134, and is biased outwardly by a spring 257. Button 253 extendsthrough an axial channel 259 in actuator handle 249, and has an enlargedinner portion 263 which is slidably received within detents 265 atspaced-apart positions along channel 259. In this way, button 253 islocked in position when enlarged inner portion 263 is received indetents 265, and to move delivery shaft 134, button 253 is pushed inwardand either proximally (to deploy repair device 130D) or distally (toretact repair device 130D). Detents 265 are positioned so as tocorrespond respectively with repair device 130D being fully retractedwithin delivery shaft 134, distal patch 244 being deployed from deliveryshaft 134, and struts 252 being deployed from delivery shaft 134.Introducer shaft 268 extends out of the proximal end of delivery shaft134 and is rotatably mounted to the proximal end of actuator handle 249.A rotatable knob 267 is mounted near the proximal end of introducershaft 268 and is exposed through a slot 269 in the side of actuatorhandle 249 to allow rotation of introducer shaft 268 for decoupling fromrepair device 130D. Retraction wires 270 extend through the interior ofintroducer shaft 268 and extend out of actuator handle 249 through ahole 271 in the proximal end thereof.

[0132]FIGS. 26A and 26B illustrate the deployment of defect repairdevice 130D of FIGS. 24A-24B. Repair device 130D is delivered throughaccess device 22 (not shown) into the heart in the collapsedconfiguration of FIG. 25 within delivery shaft 134. In the case of anatrial septal defect, delivery shaft 134 is introduced so that itsdistal end 136 is on the left atrial side of septum S, as shown in FIG.26A. Introducer shaft 268 is then advanced distally relative to deliveryshaft 134 until patch 244 is deployed from the distal end 136 of thedelivery shaft. Upon deployment, distal struts 260 and/or frame 246 (notshown) of patch 244 spring outwardly to an expanded configuration inwhich patch 244 is generally flat and parallel to septum S within theleft atrium. Delivery shaft 134 and introducer shaft 268 are then pulledproximally so that patch 244 engages septum S and points 258 on distalstruts 260 penetrate into septum S. Delivery shaft 134 is then pulledfurther proximally relative to introducer shaft 268 so that struts 252are deployed from delivery shaft 134, allowing them to spring outwardlyand toward septum S, anchoring patch 244 in position as shown in FIG.26B.

[0133] If the position of patch 244 is not satisfactory, retractionwires 270 may be tensioned to retract struts 252 back into deliveryshaft 136. Introducer shaft 268 may then be pulled proximally to retractpatch 244 back into the delivery shaft, or introducer shaft 268 may bepushed distally to disengage patch 244 from septum S, then manipulatedto reposition the patch at the desired location. Struts 252 are thenre-deployed in the manner described above. Once patch 244 is positionedsatisfactorily on septum S, retraction wires 270 are removed from struts252, introducer shaft 268 is decoupled from hub 250, and the introducershaft and delivery shaft 134 are removed from the heart. Access device22 is then removed from the heart, the penetration in the heart wall isclosed, and the procedure completed as described above.

[0134] It should be noted that in any of the foregoing embodiments ofdefect repair device 130, a portion of the patient's own pericardium maybe excised and mounted to the frame or struts of the defect repairdevice as a patch. In an exemplary embodiment, endoscopic scissors andgraspers are introduced through access ports 90 and used to cut andremove a portion of pericardium of suitable size to cover the septaldefect. Exterior to the chest cavity, the pericardial patch is thensutured onto a wire frame similar to frames 224, 226, 228 of FIGS.21-23, or onto struts like struts 252, 260 of FIGS. 24-26. If desired,two pericardial patches may be mounted to two frames or two sets ofstruts interconnected by a hub to provide patches on both sides of thecardiac septum. Once the pericardial patch is attached to the frame orstruts, the defect repair device is introduced into the heart throughaccess device 22 and attached to the cardiac septum as described above.Advantageously, the use of the patient's own pericardium reduces therisk of biologic incompatibility and other potential complications ofartificial patch materials.

[0135] In another embodiment of the invention, illustrated in FIGS.27-33, an apparatus and method are provided for closure of septaldefects using sutures, rather than patch-type defect repair devices. Inthis embodiment, a plurality of needles 274 are mounted to a distal end276 of an introducer shaft 278. Needles 274 are held parallel tointroducer shaft 278 in a generally circular arrangement coaxial withthe introducer shaft. Needles 274 may be between 2 and 12 in number, andpreferably are 4, 6, or 8 in number, depending upon the size of thedefect to be closed. A length of suture thread 275 (best seen in FIG.28) extends between each pair of needles 274, each pair having oneneedle on opposite sides of an imaginary line separating needles 274into two equal groups.

[0136] Introducer shaft 278 is preferably a rigid material such asstainless steel for optimum control in manipulating and positioningneedles 274 from outside of the chest cavity. Alternatively, all or adistal portion of introducer shaft 278 may be a flexible material andmay include means for deflecting or steering distal end 276, such aspull wires anchored internally to distal end 276 and extending throughthe introducer shaft to an actuator at the proximal end for selectivelytensioning the pull wires. Introducer shaft 278 may be used to introduceneedles 274 through access device 22 into the right atrium RA, andthrough septal defect D into left atrium LA, as illustrated in FIG. 27.Needles 274 have sharp distal tips 280 oriented so as to point in aproximal direction toward septum S from left atrium LA, and are heldremovably at their proximal ends 282 in needle holders 284 extendingdistally from the distal end of introducer shaft 278. Needle holders 284comprise flexible rods of stainless steel, titanium, Nitinol® (RaychemCorp.), or a biocompatible polymer, having a needle holding cup 285(seen more clearly in FIGS. 28-29) at their distal ends in which needles274 are inserted.

[0137] An expandable element 286 is disposed concentrically within thespace surrounded by needles 274 distal to introducer shaft 278.Expandable element 286 may comprise an inflatable balloon having aninterior in communication with an inflation tube 288 extending throughan inner lumen in introducer shaft 278. Alternatively, expandableelement 286 may comprise a rigid camming element such as a disk,cylinder, or ball fixed to the end of a movable shaft 288.

[0138] As illustrated in FIG. 28, expandable element 286 is expanded by,e.g., introducing an inflation fluid through inflation tube 288.Expandable member 286 urges needle holders 284 outward so that distaltips 280 are pointed toward septum S around the periphery of defect D.

[0139] With needle holders 284 in a radially-expanded position,introducer shaft 278 is drawn proximally relative to access device 22 sothat needle distal tips 280 penetrate septum S, as shown in FIGS.29A-29B. It can be seen that cups 285 on needle holders 284 are held inan offset relationship to flexible rods 287 so that when rods 285 engageseptum S at the periphery of defect D, needles 274 are spaced outwardlya predetermined distance from the edge of the defect to ensure adequatespacing and “bite” on the septal tissue. Preferably, each needle 274penetrates septum S about 1-3 mm from the edge of defect D.

[0140] As best seen in FIG. 29B, introducer shaft 278 may comprise aplurality of axial tubes 290 in which needle holders 284 are disposed.Needle holders 284 are slidable within tubes 290 so that needles 274 maybe moved proximally relative to tubes 290 until distal tips 280 enterthe open distal ends 292 of tubes 290. A distal portion of tubes 290 maybe flared or widened to facilitate receiving needles 274. A means forcapturing needles 274 (not shown) is provided within tubes 290 neardistal ends 292, such as a porous mesh or screen of a biocompatiblematerial such as Gore-Tex®, cotton, or Dacron, which may be penetratedby distal tips 280 of needles 274. A barb 294 is provided on needles 274just proximal to distal tips 280 which may be caught in the needlecapturing means within tubes 290 to retain needles 274 therein. Onceneedles 274 are captured within tubes 290, introducer shaft 278 is drawnproximally relative to needle holders 284, pulling needles 274 throughseptum S. Expandable member 286 may then be deflated, and expandablemember 286 along with needle holders 284 are then pulled proximallythrough defect D. Introducer shaft 278 (to which needles 274 areattached at distal ends 290), introducer shaft 278, and inflation tube288 are then withdrawn from the heart through access device 22.

[0141] In an alternative embodiment, illustrated in FIGS. 30A-30B, themeans for capturing needles 290 comprises an outer sleeve 296 slidablydisposed over introducer shaft 278. Outer sleeve 296 has a capture disk298 on its distal end which has a penetrable outer layer 300 comprisinga porous mesh, sponge, or screen of a biocompatible material such asGore-Tex®. cotton, or Dacron. To capture needles 274, as shown in FIG.30A, expandable member 286 is deflated, and outer sleeve 296 is sliddistally over introducer shaft 278 until distal tips 280 of needles 274penetrate outer layer 300 of capture disk 298. Barbs 294 are caught inthe porous material of outer layer 300. Outer sleeve 296 may then bedrawn proximally relative to introducer shaft 278 as shown in FIG. 30B,pulling needles 274 through septum S. Expandable member 286 and needleholders 284 are then withdrawn through defect D. Outer sleeve 296 (towhich needles 274 are attached), introducer shaft 278, and inflationtube 288 are then withdrawn from the heart through access device 22.

[0142] Capture disk 298 may be a flexible foam or solid material such asnatural or synthetic rubber (e.g. silicone), thermoplastic elastomer, orpolyurethane so as to be collapsible for introduction and removal fromthe heart through access device 22. Alternatively, capture disk 298 maybe an expandable member such as an inflatable balloon or expandablebasket which allows introduction and removal through access device 22 ina collapsed state, and expansion into an expanded state within the heartfor capturing needles 274. In either case, capture disk 298 hassufficient rigidity when expanded to allow needles 274 to penetrateouter layer 300 without the capture disk over-flexing or collapsing.

[0143] As a further alternative technique for capturing needles 274after they have penetrated septum S, needles 274 are removed from cups285 by pushing distally on needle holders 284. Expandable member 286 isthen deflated and withdrawn through defect D along with needle holders284. Introducer shaft 278, inflation tube 288 and needle holders 284 arethen withdrawn from the heart through access device 22, leaving needles274 extending through septum S. An elongated endoscopic needle driver(not shown) may then be introduced through access device 22 into theheart, and, under visualization with ultrasound, a endoscope, orfluoroscope, the needle driver is used to grasp each needle 274 and pullit through septum S and out of the heart through access device 22.

[0144] When needles 274 have been withdrawn from the heart, at leastone, and usually two to six loops of suture (depending upon the numberof needle pairs used), will have been formed across defect D, asillustrated in FIGS. 31A-31B. Suture threads 275 are long enough,usually at least about 30 cm in length, to extend across defect D andthrough septum S. with both ends extending out of the heart and chestcavity through access device 22. In this way, sutures 275 may betensioned to draw defect D closed, and knots formed extracorporeally andpushed into the heart through access device 22 using an elongatedendoscopic knot pusher. As shown in FIG. 31C, a plurality of knots 304are formed in each suture 275 and pushed against septum S to ensuretight closure of defect D. Sutures 275 are then trimmed using elongatedendoscopic scissors introduced through access device 22. Completeclosure and absence of shunting is verified using transesophagealechocardiography or one of the other visualization techniques outlinedabove.

[0145] An alternative embodiment of a septal defect repair deviceaccording to the invention is illustrated in FIGS. 32A-32D. Thisembodiment of defect repair device 130 is in many respects similar tothat described above in connection with FIGS. 27-30, the majordifference being that needle holders 284 are pre-shaped so as to bebiased outward into the radially-expanded configuration shown in FIG.32B. Needle holders 284 may be stainless steel, a shape-memory alloysuch as nickel-titanium, or another flexible and resilient metal orpolymer. Needle holders 284 may be long enough to extend entirely out ofthe body cavity through access device 22, or they may be attached to anintroducer shaft (not shown) as in the above embodiments. As shown inFIG. 32A, a restraining sleeve 306 is slidably positioned over needleholders 284 and may be advanced distally relative to the needle holdersto urge needle holders 284 inward into a collapsed position forintroduction through access device 22 and through defect D. A distalportion of needle holders 284 is pre-shaped in an outward bend or curveso that, when restraining sleeve 306 is retracted, needle holders 284return to a radially-expanded position in which needles 274 arepositioned outside of a circle defined by the diameter of defect D. Asin previous embodiments, needle holding cups 285 are offset relative torods 287 of needle holders 284 so that needle holders 284 move outwarduntil rods 287 engage septum S at the periphery of defect D. Needles 274are then positioned at a predetermined spacing from the edge of defect Dto ensure adequate “bite” into septal tissue.

[0146] The embodiment of the defect repair device of FIGS. 32A-32D isotherwise similar to the embodiments of FIGS. 27-31 described above. Asshown in FIGS. 32C-32D, after needles 274 have been drawn through septumS around defect D, the needles are captured by means of a capture disk298 with a porous outer layer 300, or by another means such asendoscopic needle drivers introduced through access device 22, asdescribed above. After capture of needles 274, restraining sleeve 306 isadvanced distally to collapse needle holders 284 inward, and needleholders 284, restraining sleeve 306, capture disk 298, and needles 274are withdrawn from the heart through access device 22. This leavessutures 275 extending across defect D as shown in FIGS. 31A-31B; sutures275 are then tensioned, knots are formed in sutures 275extracorporeally, and the knots are pushed into the heart and againstseptum S using an endoscopic knot pusher, closing defect D asillustrated in FIG. 31C. A suitable knot pusher is disclosed incopending application Ser. No. 08/288,674, entitled “Surgical KnotPusher and Method of Use,” filed Aug. 10, 1994, the disclosure of whichis hereby incorporated herein by reference.

[0147] It should be noted that while the method of the invention hasbeen described in connection with the repair of atrial septal defects,it will be understood to those of ordinary skill in the art that theinvention will be equally applicable to repair of ventricular septaldefects, patent ductus arteriosus, and other defects of the heart.Access device 22 may also be introduced through a wall of the rightventricle, left atrium, pulmonary artery, or pulmonary vein rather thanthe right atrium. Alternatively, access device 22 may be introduced intothe right atrium as previously described, with access to the rightventricle or pulmonary artery obtained from the right atrium through thetricuspid valve. Devices and techniques similar to those described abovefor atrial septal defects may be used for repairing ventricular defectsand patent ductus arteriosus. Other repair devices designed specificallyfor ventricular septal defects and patent ductus arteriosus which areuseful in the method of the present invention are described in U.S. Pat.No. 3,874,388, which has been incorporated herein by reference. Thedefect repair devices of the invention may also be used to repair thepenetration in the heart wall made by access device 22, and to repairother types of defects, holes, incisions, or punctures in other organsand tissue structures.

[0148] In addition to repair of atrial and ventricular septal defectsand patent ductus arteriosus, the devices and methods of the inventionalso facilitate various other intracardiac interventions, includingelectrophysiological mapping and ablation. FIGS. 33 and 34 illustratetwo embodiments of an electrophysiological device according to theinvention. In the embodiment of FIG. 33, an electrophysiology device 310is introduced through access device 22 into a chamber C of the heart H.Electrophysiology device 310 includes a rigid shaft 312 having a distalend 314 and a proximal end 316. Usually, at least one inner lumen (notshown in FIG. 33) extends through shaft 312 between distal end 314 andproximal end 316. A flexible and pre-shaped or deflectable tip 318 isattached to distal end 314. A handle 320 is attached to proximal end316. A plurality of conductive electrode bands 322 are mounted todeflectable tip 318, each electrode band being separately electricallycoupled by means of wires (not shown) within shaft 312 to a connector324 on handle 320. Connector 324 is adapted to be coupled to a cord 326which is connected to a radiofrequency generator or electrocardiographymachine (not shown) used in conventional mapping and ablationprocedures. An actuator 328 is slidably coupled to handle 320 and isconnected to deflectable tip 318 by at least one pull wire (not shown)extending slidably through an inner lumen in shaft 312 and attachedinternally to deflectable tip 318 near its distal end 330. In this way,sliding actuator 328 proximally on handle 320 deflects deflectable tip318 into a curved configuration, as illustrated in FIG. 33. Of course,various types of actuators may be used for deflection of deflectable tip318, including shapable or deflectable handles, joy-sticks, levers,pistol grips, and the like. In addition, shaft 312 may be rotatablycoupled to handle 320, and a rotator knob (not shown) may be attached toshaft 312 near proximal end 316 to allow deflectable tip 318 to berotated about the longitudinal axis of shaft 312. Exemplary mechanismsfor actuation and deflection of deflectable tip 318 and other featureswhich may be incorporated into electrophysiology device 310 aredisclosed in U.S. Pat. Nos. 4,960,134, 5,318,525, 5,368,592, 5,364,351,and 5,313,943, which are incorporated herein by reference. While thesepatents disclose highly flexible, endovascular electrophysiologycatheters for introduction transluminally from a peripheral vessel intothe heart, it will be understood to those of ordinary skill in the artthat any of the features of endovascular electrophysiology devices maybe easily incorporated into the more rigid, thoracoscopicelectrophysiology device of the invention.

[0149] Shaft 312 has a length which is long enough to extend from withinchamber C of heart H through access device 22 outside of the patient,usually being 20-30 cm in length. Shaft 312 is preferably rigid, usuallybeing made of stainless steel (with insulated electrodes and wires) orof a rigid biocompatible polymer, so as to facilitate precise andcontrollable positioning of deflectable tip 318 from outside of thechest cavity using handle 320. Deflectable tip 318 is a non-conductive,flexible and biocompatible polymer such as polyurethane, silicone,thermoplastic elastomer, polyolefin, polyamide, or a fluoropolymer.

[0150] In an alternative embodiment, illustrated in FIG. 34,electrophysiology device 310 includes, rather than a deflectable tip 318as in the previous embodiment, an expandable electrode array 332attached to distal end 314 of shaft 312. In a preferred embodiment,electrode array 332 comprises a plurality of electrode bands 334 mountedin spaced-apart positions to an expandable basket 336. Expandable basket336 includes a plurality of axially-oriented beams 338, which arepreferably a non-conductive, flexible and resilient polymer such as apolyolefin or polyamide, or a metal such as stainless steel ornickel-titanium alloy with an insulative coating to electrically isolateeach of electrode bands 334. Beams 338 are coupled together at theirdistal ends 340, and at their proximal ends are attached to shaft 312.In one embodiment, shaft 312 is a polymeric tubular extrusion, and beams338 are formed integrally with shaft 312 as part of the same extrusion,by, for example cutting axial slits in a distal portion of shaft 312. Asin the embodiment of FIG. 33, each of electrode bands 334 isindependently electrically coupled to connector 324 by a wire extendingthrough an inner lumen in shaft 312.

[0151] Expandable basket 336 is movable between a collapsedconfiguration suitable for introduction through access device 22 and anexpanded configuration in which electrode bands 334 are spread apartinto a three-dimensional array, positioned at various distances bothradially outward from and distal to shaft 312, as shown in FIG. 34. Inthis way, electrode bands 334 may be simultaneously positioned at anumber of locations around the interior wall of chamber C. To moveexpandable basket 336 between the collapsed and expanded configurations,a variety of different mechanisms may be utilized. In one embodiment, apull wire 342 is coupled to distal ends 340 of beams 338, and extendsslidably through a lumen in shaft 312 for attachment to actuator 328. Inthis way, actuator 328 may be slid in a proximal direction to exert acompressive force on beams 338, causing beams 338 to bow outward intothe expanded configuration. When pressure is released from actuator 328,beams 338 recoil to their unstressed, straight configuration.

[0152] In addition to the embodiment illustrated, various types ofstructures may be used for electrode array 332, including thosedisclosed in U.S. Pat. Nos. 4,699,147, 4,660,571, 4,628,937, 4,522,212,5,313,943, and 5,327,889, which are incorporated herein by reference.Although these patents describe endovascular electrophysiologicalcatheters, it will be understood to those of ordinary skill in the artthat the electrode array configurations, structures and deploymentmechanisms disclosed may be easily adapted to the larger diameter,shorter and more rigid thoracoscopic electrophysiology device of thepresent invention.

[0153] Electrophysiology device 310 may be used for either mapping orablation of conduction pathways in the heart. In use, electrophysiologydevice 310 is introduced into chamber C of heart H through inner lumen30 of access device 22. Chamber C may be the left or right ventricle, orleft or right atrium, depending upon where the target site for mappingor ablation is located. If the target site is in the higher pressureleft side of the heart, access device 22 is provided with a hemostasisseal in inner lumen 30 to allow introduction of electrophysiology device310 without significant leakage of blood. For the device of FIG. 33,deflectable tip 318 is substantially straight and undeflected duringintroduction. For the device of FIG. 34, expandable basket 336 is in acollapsed state in which beams 338 are substantially straight andaligned with shaft 312 during introduction. Once introduced into chamberC, deflectable tip 318 is deflected (in the embodiment of FIG. 33) orexpandable basket 336 is expanded into an expanded configuration (in theembodiment of FIG. 34) by sliding actuator 328 on handle 320. Undervisualization using transesophageal echocardiography or one of the othertechniques described above, electrodes 322, 334 are positioned at thedesired location against the wall of chamber C by manipulating thedevice with handle 320. The relatively short distance between the userand the interior of chamber C, as well as the rigidity of shaft 312,facilitate exceptionally controllable and precise manipulation of thedevice relative to endovascular catheter-based electrophysiologydevices.

[0154] When electrodes 322, 334 have been positioned at the desired sitein chamber C, conduction pathways can be mapped by measuring theelectrical potential between selected electrodes with sensitiveelectrocardiographic equipment. When aberrant pathways are found, theymay be ablated by applying radiofrequency current from a radiofrequencygenerator through a selected electrode or electrodes onelectrophysiology device 310 to the myocardial tissue. These techniquesmay be used to diagnose and/or treat ventricular tachycardias,ventricular fibrillation, supraventricular tachycardias such asWolff-Parkinson-White Syndrome, atrial fibrillation, and otherconduction-related diseases. Ablation may also be performed using amedical laser transmitted through an optical fiber introduced into theheart through access device 22, by techniques analogous to theendovascular laser ablation techniques disclosed in U.S. Pat. No.5,104,393, which is incorporated herein by reference.

[0155] In addition, thoracoscopic, endovascular, or open surgicaldevices and techniques may be used in conjunction with the devices andmethods of the present invention. For example, electrophysiology device310 may be used to ablate selected cardiac tissue within the heart basedon mapping information generated using endovascular mapping catheters orthoracoscopic mapping devices. Alternatively, electrophysiology device310 may be used for mapping conduction pathways in the heart, which arethen treated by means of thoracoscopic, endovascular, or open-chesttechniques. Such a technique could be used for treatment of ventricularand supraventricular tachycardias. Similarly, to treat atrialfibrillation, after intracardiac mapping has been performed using theelectrophysiology device of the invention and/or endovascular mappingtechniques, mechanical, laser, or RF cutting devices may be introducedthrough access device 22, and precise incisions or ablation lines may bemade in the myocardium to create a directed conduction pathway betweenthe sinoatrial node and the atrioventricular node to perform a Cox“maze” procedure.

[0156] After the electrophysiology procedure is completed, deflectabletip 318 is returned to its straightened configuration or expandablebasket 336 is collapsed so that beams 338 are again straight and alignedwith shaft 312. Electrophysiology device 310 is then removed from thechest cavity through access device 22.

[0157] In addition to repair of atrial and ventricular septal defectsand cardiac mapping and ablation, the devices and techniques of theinvention are useful in a variety of other intracardiac procedures.Low-profile, elongated instruments may be introduced through accessdevice 22 to inspect and repair the mitral, tricuspid, pulmonary oraortic valves. Commissurotomy may be performed, for example, byintroducing a cutting instrument and incising the valve commissures toseparate the valve leaflets. Transmyocardial laser revascularization maybe performed by introducing a laser-transmitting optical fiber throughaccess device 22 and using the laser to drill new blood-carryingconduits into the myocardium from within the heart chambers. Cutters,graspers, biters, and the like may be introduced through access device22 to cut and remove unwanted tissue or other material from the heartand great vessels, such as thrombus (e.g. pulmonary thrombectomy),myxomas, neoplasms, vegetations, calcifications, and tissues affected byhypertrophic obstructive cardiopmyopathy. Catheters may also beintroduced through access device 22 for positioning in the pulmonaryartery, coronary sinus, or other locations for perfusion, drug delivery,fluid venting, and other purposes. Advantageously, many of theseprocedures can be performed while the heart is beating, without the needto place the patient on cardiopulmonary bypass and to inducecardioplegic arrest. In addition, these procedures can be performedwithout the need for a median sternotomy or other gross thoracotomy,reducing greatly the pain, recovery time, morbidity, and mortalityassociated with open heart surgery.

[0158] While the above is a complete description of the preferredembodiments of the invention, it will be understood to one of ordinaryskill in the art that certain modifications, substitutions, improvementsand additions may be made without departing from the scope thereof,which is defined by the appended claims.

What is claimed is:
 1. A method for accessing an interior chamber of abeating heart, said method comprising: forming a penetration through amuscular wall of the heart into the interior chamber; positioning adistal end of a tubular access device having an inner lumen through thepenetration; and forming a hemostatic seal between the device and thepenetration to inhibit blood loss through the penetration.
 2. A methodas in claim 1 wherein the interior chamber is selected from a rightatrium, a right ventricle, and a left atrium.
 3. A method as in claim 2,wherein a proximal end of the tubular access device is open to theexterior and wherein blood flow through the inner lumen is prevented bythe pressure head of blood within the inner lumen.
 4. A method as inclaim 3, wherein a lateral side of the patient is disposed upward topermit vertical entry of the tubular access device into the interiorchamber from a lateral portion of the chest.
 5. A method as in claim 1,wherein the tubular access device is introduced percutaneously throughan intercostal space.
 6. A method as in claim 5, wherein the tubularaccess device is passed percutaneously through an intercostal spaceselected from the second, third, fourth, fifth, sixth or seventhintercostal space.
 7. A method as in claim 1, wherein a lung iscollapsed to provide a working space between the ribs and thepericardium.
 8. A method as in claim 7, further comprisingpercutaneously introducing a viewing scope into the working space andviewing the heart while forming the penetration and positioning thedistal end of the access device.
 9. A method as in claim 8, wherein theheart is viewed by viewing a video image obtained from a camera mountedto the viewing scope.
 10. A method as in claim 8, wherein the heart isdirectly viewed through an optical passage in the viewing scope.
 11. Amethod as in claim 1, wherein the hemostatic seal is formed by expandinga balloon around the access device to occlude the penetration.
 12. Amethod as in claim 1, wherein the hemostatic seal is formed by radiallyexpanding the access device.
 13. A method as in claim 1, wherein thehemostatic seal is formed by tightening a purse-string suture in theheart wall around the penetration.
 14. A method as in claim 1, furthercomprising performing a procedure on the heart using one or moreinstruments introduced through the inner lumen of the access device. 15.A method for closing a cardiac septal defect in a heart, said methodcomprising: positioning a tubular access device percutaneously throughan intercostal space and through a penetration in a muscular wall of theheart; and passing one or more instruments from a proximal end of theaccess device, through an inner lumen of the access device, and out of adistal end of the access device into a cardiac chamber in the heart,wherein the one or more instruments are used to close the septal defect.16. A method as in claim 15, wherein the cardiac septal defect is closedby applying at least one suture to the cardiac septum using a suturinginstrument introduced into the cardiac chamber through the inner lumenof the access device.
 17. A method as in claim 16, wherein the step ofapplying at least one suture comprises: inserting through the defect aplurality of needles connected by at least one length of suture, theneedles being inserted while in a retracted position; repositioning theneedles to a radially expanded position; drawing the needles through thecardiac septum while in the radially expanded position to position thelength of suture across the defect; and tensioning the length of sutureto close the defect.
 18. An improved method for closing a cardiac septaldefect of the type in which a patch of material is secured over thedefect, wherein the improvement comprises introducing and securing thepatch through an inner lumen of a tubular access device positionedthrough a muscular wall of the heart.
 19. An improved method for closinga cardiac septal defect of the type in which a pericardium patch issecured over the defect, wherein the improvement comprises harvestingthe pericardium patch using instruments introduced through one or moreintercostal spaces, and introducing and securing the patch in the heartthrough an inner lumen of a tubular access device positioned through amuscular wall of the heart.
 20. An improved method for closing a cardiacseptal defect of the type in which the defect is sutured closed, whereinthe improvement comprises suturing the defect using an instrumentintroduced through an inner lumen of a tubular access device positionedthrough a muscular wall of the heart.
 21. A method of forming a lesionin heart tissue of a patient, comprising: providing anelectrophysiological ablating device comprising at least one electrode;forming an opening in a patient's chest, the opening passing through thechest wall and into the patient's thoracic cavity; passing the electrodethrough the opening; postioning the electrode adjacent to heart tissue;and ablating the heart tissue with the electrode to create a lesion inthe heart tissue.
 22. The method of claim 21, comprising the steps of:forming a second opening in the wall of the patient's heart, the secondopening passing through the wall of the heart and into an interiorchamber of the heart; positioning the electrode through the secondopening and within an interior chamber of the heart prior to the step ofablating the heart tissue with the electrode.
 23. The method of claim22, wherein the step of positioning the electrode within a chamber ofthe patient's heart comprises the steps of: introducing a tubular accessdevice into the second opening, the access device having an inner lumenand a distal end; inserting the electrophysiological ablation devicethrough the inner lumen of the tubular access device such that theelectrode extends beyond the distal end of the access device and withinan interior chamber of the heart.
 24. The method of claim 21, whereinthe opening is formed intercostally and the electrophysiologicalablation device is introduced through the intercostal space.
 25. Themethod of claim 21, wherein the step of ablating the heart tissue isperformed while the heart is beating.
 26. A method of ablating cardiactissue, comprising: inserting an ablation device into a chamber of apatient's heart through a penetration formed in a wall of the heart, theablation device having a distal end adapted to transmit ablative energy;positioning the distal end of the ablation device at a desired sitewithin the chamber of the heart; applying ablative energy to the cardiactissue to form at least one lesion.
 27. The method of claim 26, whereinthe distal end of the ablation device is positioned adjacent anendocardial surface of the patient's heart.
 28. The method of claim 26,wherein the electrode is positioned within the left atrium of the heart,and the at least one lesion is formed on the endocardial surface of theleft atrium.
 29. The method of claim 26, wherein the electrode ispositioned within the right atrium of the heart, and the at least onelesion is formed on the endocardial surface of the right atrium.
 30. Amethod of forming a lesion in heart tissue of a patient, comprising:providing an electrophysiological ablating device comprising an ablatingelement; forming an opening in a patient's chest, the opening passingthrough the chest wall and into the patient's thoracic cavity;positioning the ablating element through the opening so that theablating element is disposed adjacent heart tissue; and ablating theheart tissue with the ablating element to create a lesion in the hearttissue.
 31. The method of claim 30, wherein the step of ablating theheart tissue comprises the step of applying radiofrequency energy tocreate the lesion in the heart tissue.
 32. The method of claim 30,wherein the step of ablating the heart tissue comprises the step ofapplying microwave energy to create the lesion in the heart tissue. 33.The method of claim 30, wherein the step of ablating the heart tissuecomprises the step of applying ultrasound energy to create the lesion inthe heart tissue.
 34. The method of claim 30, wherein the step ofablating the heart tissue comprises the step of applying laser energy tocreate the lesion in the heart tissue.
 35. The method of claim 30,wherein the step of ablating the heart tissue comprises the step ofapplying direct current to create the lesion in the heart tissue. 36.The method of claim 30, wherein the step of ablating the heart tissuecomprises the step of applying cyrogenic energy to create the lesion inthe heart tissue.
 37. The method of claim 30, comprising the steps of:forming a second opening in the wall of the patient's heart, the secondopening passing through the wall of the heart and into an interiorchamber of the heart; positioning the ablating element through thesecond opening prior to the step of ablating the heart tissue with theablating element.